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Retirement Plans and Postretirement Benefit Plans (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2015 | Sep. 30, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Pension Contributions |  |  |  | $ 20.0 | $ 0.0 |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  |  |  | 200.00% |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  |  |  | 5.00% |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Net periodic benefit cost |  |  |  | $ 22.5 | 40.2 | $ 19.3
Effect of One Percentage Point Increase on Service and Interest Cost Components |  |  |  | 0.0 | 0.0 | 0.0
Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation |  |  |  | 0.2 | 0.2 | 0.1
Effect of One Percentage Point Decrease on Service and Interest Cost Components |  |  |  | 0.0 | 0.1 | 0.1
Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation |  |  |  | 0.7 | 0.7 | 0.7
Expected Future Benefit Payments, Next Twelve Months |  |  |  | 48.7 |  |
Expected Future Benefit Payments, Year Two |  |  |  | 48.7 |  |
Expected Future Benefit Payments, Year Three |  |  |  | 51.9 |  |
Expected Future Benefit Payments, Year Four |  |  |  | 54.6 |  |
Expected Future Benefit Payments, Year Five |  |  |  | 55.7 |  |
Expected Future Benefit Payments, Five Fiscal Years Thereafter |  |  |  | 290.1 |  |
Defined Contribution Plan, Cost Recognized |  |  |  | 11.9 | 11.6 | 15.2
Pension Plans, Defined Benefit [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Accumulated Benefit Obligation |  | $ 610.9 |  | 608.0 | 610.9 |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |  |  |
Benefit Obligation, Beginning |  |  |  | 680.0 | 725.0 |
Service cost |  |  |  | 15.8 | 16.1 | 15.3
Interest cost |  |  |  | 25.5 | 26.1 | 28.1
Plan settlements |  |  |  | 0.0 | (60.7) |
Participants' contributions |  |  |  | 0.0 | 0.0 |
Actuarial gains (losses) |  |  |  | 4.7 | (11.3) |
Benefits paid |  |  |  | (53.8) | (15.2) |
Benefit Obligation, Ending |  | 680.0 |  | 672.2 | 680.0 | 725.0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 581.7 | 679.8 |
Actual return on plans' assets |  |  |  | 48.0 | (22.2) |
Employer contributions |  |  |  | 20.0 | 0.0 |
Plan settlements |  |  |  | 0.0 | (60.7) |
Participants' contributions |  |  |  | 0.0 | 0.0 |
Benefits paid |  |  |  | (53.8) | (15.2) |
Fair Value of Plan Assets, Ending |  | 581.7 |  | 595.9 | 581.7 | 679.8
Funded Status of Plan |  | (98.3) |  | (76.3) | (98.3) |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Service cost |  |  |  | 15.8 | 16.1 | 15.3
Interest cost |  |  |  | 25.5 | 26.1 | 28.1
Expected return on plan assets |  |  |  | (41.5) | (46.0) | (45.3)
Amortization of net loss |  |  |  | 16.5 | 18.0 | 14.3
Amortization of unrecognized prior service cost | [1] |  |  | (0.1) | 0.4 | 1.7
Curtailment |  |  |  | 0.0 | 0.0 | (0.2)
Settlement |  | $ 5.5 | $ 16.2 | 0.0 | 21.7 | 0.0
Net periodic benefit cost |  |  |  | 16.2 | 36.3 | 13.9
Amount paid by unconsolidated affiliates |  |  |  | 5.1 | 4.2 | 3.2
Net Periodic Benefit Cost, Net of Unconsolidated Affiliates | [2] |  |  | 11.1 | 32.1 | 10.7
Plan settlements |  |  |  | 0.0 | (60.7) |
Capitalized Portion of Net Periodic Benefit Cost |  |  |  | $ 4.0 | $ 5.0 | $ 3.4
Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 4.00% |  | 4.00% | 4.00% | 3.80%
Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets |  |  |  | 7.50% | 7.50% | 7.50%
Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase |  |  |  | 4.20% | 4.20% | 4.20%
Fair Value of Plan Assets, Beginning |  |  |  | $ 581.7 | $ 679.8 |
Pension Plans, Defined Benefit [Member] | OKLAHOMA |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Additional Pension Expense to Meet State Requirements |  |  |  | 9.9 | (3.1) | $ 11.2
Pension Plans, Defined Benefit [Member] | ARKANSAS |  |  |  |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |  |  |
Plan settlements |  |  |  | 0.1 | 1.9 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Plan settlements |  |  |  | 0.1 | 1.9 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Plan settlements |  |  |  | 0.1 | 1.9 |
Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | $ 0.0 |  |  | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | U.S. common stocks [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 208.2 |  |
Fair Value of Plan Assets, Ending |  | 208.2 |  | 237.1 | 208.2 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 208.2 |  |
Pension Plans, Defined Benefit [Member] | U.S. common stocks [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 208.2 |  |
Fair Value of Plan Assets, Ending |  | 208.2 |  | 237.1 | 208.2 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 208.2 |  |
Pension Plans, Defined Benefit [Member] | U.S. common stocks [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | U.S. treasury notes and bonds [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure | [3] | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [3] |  |  | 158.9 |  |
Fair Value of Plan Assets, Ending | [3] | 158.9 |  | 122.3 | 158.9 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [3] |  |  | 158.9 |  |
Pension Plans, Defined Benefit [Member] | U.S. treasury notes and bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [3] |  |  | 158.9 |  |
Fair Value of Plan Assets, Ending | [3] | 158.9 |  | 122.3 | 158.9 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [3] |  |  | 158.9 |  |
Pension Plans, Defined Benefit [Member] | U.S. treasury notes and bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [3] |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending | [3] | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [3] |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Mortgage-backed securities |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 14.5 |  |
Fair Value of Plan Assets, Ending |  | 14.5 |  | 59.2 | 14.5 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 14.5 |  |
Pension Plans, Defined Benefit [Member] | Mortgage-backed securities | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Mortgage-backed securities | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 14.5 |  |
Fair Value of Plan Assets, Ending |  | 14.5 |  | 59.2 | 14.5 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 14.5 |  |
Pension Plans, Defined Benefit [Member] | Corporate fixed income and other securities [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 140.2 |  |
Fair Value of Plan Assets, Ending |  | 140.2 |  | 137.6 | 140.2 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 140.2 |  |
Pension Plans, Defined Benefit [Member] | Corporate fixed income and other securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Corporate fixed income and other securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 140.2 |  |
Fair Value of Plan Assets, Ending |  | 140.2 |  | 137.6 | 140.2 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 140.2 |  |
Pension Plans, Defined Benefit [Member] | Commingled fund [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure | [4] | 24.4 |  | 23.8 | 24.4 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [4] |  |  | 24.4 |  |
Fair Value of Plan Assets, Ending | [4] | 24.4 |  | 23.8 | 24.4 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [4] |  |  | 24.4 |  |
Pension Plans, Defined Benefit [Member] | Commingled fund [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [4] |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending | [4] | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [4] |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Commingled fund [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [4] |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending | [4] | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [4] |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Foreign government bonds [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 5.6 |  |
Fair Value of Plan Assets, Ending |  | 5.6 |  | 5.2 | 5.6 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 5.6 |  |
Pension Plans, Defined Benefit [Member] | Foreign government bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Foreign government bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 5.6 |  |
Fair Value of Plan Assets, Ending |  | 5.6 |  | 5.2 | 5.6 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 5.6 |  |
Pension Plans, Defined Benefit [Member] | Interest-bearing cash [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  |  | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.4 |  |
Fair Value of Plan Assets, Ending |  | 0.4 |  |  | 0.4 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.4 |  |
Pension Plans, Defined Benefit [Member] | Interest-bearing cash [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.4 |  |
Fair Value of Plan Assets, Ending |  | 0.4 |  |  | 0.4 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.4 |  |
Pension Plans, Defined Benefit [Member] | Interest-bearing cash [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  |  | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Municipal bonds [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 4.9 |  |
Fair Value of Plan Assets, Ending |  | 4.9 |  | 1.9 | 4.9 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 4.9 |  |
Pension Plans, Defined Benefit [Member] | Municipal bonds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Municipal bonds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 4.9 |  |
Fair Value of Plan Assets, Ending |  | 4.9 |  | 1.9 | 4.9 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 4.9 |  |
Pension Plans, Defined Benefit [Member] | Money market funds [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 11.7 |  | 2.2 | 11.7 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 11.7 |  |
Fair Value of Plan Assets, Ending |  | 11.7 |  | 2.2 | 11.7 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 11.7 |  |
Pension Plans, Defined Benefit [Member] | Money market funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Money market funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Mutual fund [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 24.3 |  |
Fair Value of Plan Assets, Ending |  | 24.3 |  | 9.0 | 24.3 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 24.3 |  |
Pension Plans, Defined Benefit [Member] | Mutual fund [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 24.3 |  |
Fair Value of Plan Assets, Ending |  | 24.3 |  | 9.0 | 24.3 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 24.3 |  |
Pension Plans, Defined Benefit [Member] | Mutual fund [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Treasury futures, receivable [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 17.6 |  |
Fair Value of Plan Assets, Ending |  | 17.6 |  | 10.7 | 17.6 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 17.6 |  |
Pension Plans, Defined Benefit [Member] | Treasury futures, receivable [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Treasury futures, receivable [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 17.6 |  |
Fair Value of Plan Assets, Ending |  | 17.6 |  | 10.7 | 17.6 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 17.6 |  |
Pension Plans, Defined Benefit [Member] | Treasury futures, payable [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (12.4) |  |
Fair Value of Plan Assets, Ending |  | (12.4) |  | (2.3) | (12.4) |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (12.4) |  |
Pension Plans, Defined Benefit [Member] | Treasury futures, payable [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Treasury futures, payable [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (12.4) |  |
Fair Value of Plan Assets, Ending |  | (12.4) |  | (2.3) | (12.4) |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (12.4) |  |
Pension Plans, Defined Benefit [Member] | Cash collateral [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  |  |  | 0.0 |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  |  |  | 0.3 |  |
Pension Plans, Defined Benefit [Member] | Cash collateral [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  |  |  | 0.3 |  |
Pension Plans, Defined Benefit [Member] | Cash collateral [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Receivable (foreign currency) [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.1 |  |
Fair Value of Plan Assets, Ending |  | 0.1 |  | 0.2 | 0.1 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.1 |  |
Pension Plans, Defined Benefit [Member] | Receivable (foreign currency) [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Receivable (foreign currency) [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.1 |  |
Fair Value of Plan Assets, Ending |  | 0.1 |  | 0.2 | 0.1 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.1 |  |
Pension Plans, Defined Benefit [Member] | Payable (foreign currency) [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  |  | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (0.1) |  |
Fair Value of Plan Assets, Ending |  | (0.1) |  |  | (0.1) |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (0.1) |  |
Pension Plans, Defined Benefit [Member] | Payable (foreign currency) [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  |  | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Payable (foreign currency) [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (0.1) |  |
Fair Value of Plan Assets, Ending |  | (0.1) |  |  | (0.1) |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (0.1) |  |
Pension Plans, Defined Benefit [Member] | Index fund [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  |  | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 1.8 |  |
Fair Value of Plan Assets, Ending |  | 1.8 |  |  | 1.8 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 1.8 |  |
Pension Plans, Defined Benefit [Member] | Index fund [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 1.8 |  |
Fair Value of Plan Assets, Ending |  | 1.8 |  |  | 1.8 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 1.8 |  |
Pension Plans, Defined Benefit [Member] | Index fund [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  |  | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Preferred stocks (foreign) [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 0.0 |  |  | 0.0 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.3 |  |
Fair Value of Plan Assets, Ending |  | 0.3 |  |  | 0.3 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.3 |  |
Pension Plans, Defined Benefit [Member] | Preferred stocks (foreign) [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.3 |  |
Fair Value of Plan Assets, Ending |  | 0.3 |  |  | 0.3 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.3 |  |
Pension Plans, Defined Benefit [Member] | Preferred stocks (foreign) [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  |  | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Total Plan investments [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Alternative Investments, Fair Value Disclosure |  | 36.1 |  | 26.0 | 36.1 |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 600.4 |  |
Fair Value of Plan Assets, Ending |  | 600.4 |  | 607.2 | 600.4 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 600.4 |  |
Pension Plans, Defined Benefit [Member] | Total Plan investments [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 393.9 |  |
Fair Value of Plan Assets, Ending |  | 393.9 |  | 368.7 | 393.9 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 393.9 |  |
Pension Plans, Defined Benefit [Member] | Total Plan investments [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 170.4 |  |
Fair Value of Plan Assets, Ending |  | 170.4 |  | 212.5 | 170.4 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 170.4 |  |
Pension Plans, Defined Benefit [Member] | Receivable from broker for securities sold [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 |  |
Pension Plans, Defined Benefit [Member] | Interest and dividends receivable [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 3.5 |  |
Fair Value of Plan Assets, Ending |  | 3.5 |  | 3.0 | 3.5 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 3.5 |  |
Pension Plans, Defined Benefit [Member] | Payable to broker for securities purchased [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (22.2) |  |
Fair Value of Plan Assets, Ending |  | (22.2) |  | (14.3) | (22.2) |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | (22.2) |  |
Pension Plans, Defined Benefit [Member] | Total Plan assets [Member] |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 581.7 |  |
Fair Value of Plan Assets, Ending |  | 581.7 |  | 595.9 | 581.7 |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 581.7 |  |
Restoration of Retirement Income Plan [Member] |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Accumulated Benefit Obligation |  | 24.6 |  | 6.1 | 24.6 |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |  |  |
Benefit Obligation, Beginning |  |  |  | 25.1 | 19.7 |
Service cost |  |  |  | 0.3 | 1.3 | 1.1
Interest cost |  |  |  | 0.4 | 0.7 | 0.6
Plan settlements |  |  |  | (20.6) | 0.0 |
Participants' contributions |  |  |  | 0.0 | 0.0 |
Actuarial gains (losses) |  |  |  | 1.8 | 4.0 |
Benefits paid |  |  |  | 0.0 | (0.6) |
Benefit Obligation, Ending |  | 25.1 |  | 7.0 | 25.1 | 19.7
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  |  |  | 0.0 | 0.0 |
Actual return on plans' assets |  |  |  | 0.0 | 0.0 |
Employer contributions |  |  |  | 20.6 | 0.6 |
Plan settlements |  |  |  | (20.6) | 0.0 |
Participants' contributions |  |  |  | 0.0 | 0.0 |
Benefits paid |  |  |  | 0.0 | (0.6) |
Fair Value of Plan Assets, Ending |  | 0.0 |  | 0.0 | 0.0 | 0.0
Funded Status of Plan |  | $ (25.1) |  | (7.0) | (25.1) |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Service cost |  |  |  | 0.3 | 1.3 | 1.1
Interest cost |  |  |  | 0.4 | 0.7 | 0.6
Expected return on plan assets |  |  |  | 0.0 | 0.0 | 0.0
Amortization of net loss |  |  |  | 0.7 | 0.6 | 0.2
Amortization of unrecognized prior service cost | [1] |  |  | 0.1 | 0.1 | 0.2
Curtailment |  |  |  | 0.0 | 0.0 | 0.0
Settlement |  |  |  | 8.6 | 0.0 | 0.0
Net periodic benefit cost |  |  |  | 10.1 | 2.7 | 2.1
Amount paid by unconsolidated affiliates |  |  |  | 0.3 | 0.1 | 0.1
Net Periodic Benefit Cost, Net of Unconsolidated Affiliates | [2] |  |  | 9.8 | 2.6 | $ 2.0
Plan settlements |  |  |  | (20.6) | 0.0 |
Fair Value of Plan Assets, Beginning |  |  |  | $ 0.0 | $ 0.0 |
Less Than 90% [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Projected Benefit Obligation Funded Status Thresholds Fixed Income |  |  |  | 50.00% |  |
Projected Benefit Obligation Funded Status Thresholds Equity |  |  |  | 50.00% |  |
Projected Benefit Obligation Funded Status Thresholds |  |  |  | 100.00% |  |
95% [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Projected Benefit Obligation Funded Status Thresholds Fixed Income |  |  |  | 58.00% |  |
Projected Benefit Obligation Funded Status Thresholds Equity |  |  |  | 42.00% |  |
Projected Benefit Obligation Funded Status Thresholds |  |  |  | 100.00% |  |
100% [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Projected Benefit Obligation Funded Status Thresholds Fixed Income |  |  |  | 65.00% |  |
Projected Benefit Obligation Funded Status Thresholds Equity |  |  |  | 35.00% |  |
Projected Benefit Obligation Funded Status Thresholds |  |  |  | 100.00% |  |
105% [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Projected Benefit Obligation Funded Status Thresholds Fixed Income |  |  |  | 73.00% |  |
Projected Benefit Obligation Funded Status Thresholds Equity |  |  |  | 27.00% |  |
Projected Benefit Obligation Funded Status Thresholds |  |  |  | 100.00% |  |
110% [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Projected Benefit Obligation Funded Status Thresholds Fixed Income |  |  |  | 80.00% |  |
Projected Benefit Obligation Funded Status Thresholds Equity |  |  |  | 20.00% |  |
Projected Benefit Obligation Funded Status Thresholds |  |  |  | 100.00% |  |
115% [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Projected Benefit Obligation Funded Status Thresholds Fixed Income |  |  |  | 85.00% |  |
Projected Benefit Obligation Funded Status Thresholds Equity |  |  |  | 15.00% |  |
Projected Benefit Obligation Funded Status Thresholds |  |  |  | 100.00% |  |
120% [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Projected Benefit Obligation Funded Status Thresholds Fixed Income |  |  |  | 90.00% |  |
Projected Benefit Obligation Funded Status Thresholds Equity |  |  |  | 10.00% |  |
Projected Benefit Obligation Funded Status Thresholds |  |  |  | 100.00% |  |
Domestic All-Cap/Large Cap Equity [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Target Plan Asset Allocations |  |  |  | 40.00% |  |
Target Plan Asset Allocations Range Minimum |  |  |  | 35.00% |  |
Target Plan Asset Allocations Range Maximum |  |  |  | 60.00% |  |
Domestic Mid-Cap Equity [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Target Plan Asset Allocations |  |  |  | 15.00% |  |
Target Plan Asset Allocations Range Minimum |  |  |  | 5.00% |  |
Target Plan Asset Allocations Range Maximum |  |  |  | 25.00% |  |
Domestic Small-Cap Equity [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Target Plan Asset Allocations |  |  |  | 25.00% |  |
Target Plan Asset Allocations Range Minimum |  |  |  | 5.00% |  |
Target Plan Asset Allocations Range Maximum |  |  |  | 30.00% |  |
International Equity [Member] |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] |  |  |  |  |  |
Target Plan Asset Allocations |  |  |  | 20.00% |  |
Target Plan Asset Allocations Range Minimum |  |  |  | 10.00% |  |
Target Plan Asset Allocations Range Maximum |  |  |  | 30.00% |  |
[1] | Unamortized prior service cost is amortized on a straight-line basis over the average remaining service period to the first eligibility age of participants who are expected to receive a benefit and are active at the date of the plan amendment.
[2] | In addition to the $22.5 million, $40.2 million and $19.3 million of net periodic benefit cost recognized in 2016, 2015 and 2014, respectively, OG&E recognized the following: •a change in pension expense in 2016, 2015 and 2014 of $9.9 million, $(3.1) million and $11.2 million, respectively, to maintain the allowable amount to be recovered for pension expense in the Oklahoma jurisdiction, which are included in the Pension tracker regulatory asset or liability (see Note 1); •an increase in postretirement medical expense in 2016, 2015 and 2014 of $7.9 million, $5.8 million and $5.2 million, respectively, to maintain the allowable amount to be recovered for postretirement medical expense in the Oklahoma jurisdiction which are included in the Pension tracker regulatory asset or liability (see Note 1); and •a deferral of pension expense in 2016 and 2015 of $0.1 million and $1.9 million related to the Arkansas jurisdictional portion of the pension settlement charge of $8.6 million and $21.7 million, respectively.
[3] | This category represents U.S. treasury notes and bonds with a Moody's Investors Services rating of Aaa and Government Agency Bonds with a Moody's Investors Services rating of A1 or higher.
[4] | This category represents units of participation in a commingled fund that primarily invested in stocks of international companies and emerging markets.

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- Definition Fair value of investments in certain entities that calculate net asset value per share, including, but not limited to, by unit, membership interest, or other ownership interest. Investments include, but are not limited to, investments in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258 + Details
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- Definition For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503844 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost) -URI http://asc.fasb.org/extlink&oid=6504192 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Actual Return on Plan Assets (Component of Net Periodic Pension Cost) -URI http://asc.fasb.org/extlink&oid=6504226 + Details
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- Definition Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Gain or Loss -URI http://asc.fasb.org/extlink&oid=49168827 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Prior Service Cost -URI http://asc.fasb.org/extlink&oid=49177896 + Details
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- Definition The interest rate used to adjust for the time value of money for the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Expected Long-Term Rate of Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512046 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition 1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Projected Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6522206 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Postretirement Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503904 + Details
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- Definition The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=49170737 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Postretirement Benefits -URI http://asc.fasb.org/extlink&oid=6521376 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(5) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of contributions made by the employer to defined benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 35 -Paragraph 123 -Subparagraph B -URI http://asc.fasb.org/extlink&oid=64937487&loc=d3e36068-114959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 63 -Subparagraph B -URI http://asc.fasb.org/extlink&oid=64937038&loc=d3e12551-114930 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512171 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=64937038&loc=d3e12355-114930 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Plan Assets -URI http://asc.fasb.org/extlink&oid=6749337 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Plan Assets -URI http://asc.fasb.org/extlink&oid=6520858 + Details
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- Definition The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919 + Details
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- Definition The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Service Cost (Component of Net Periodic Pension Cost) -URI http://asc.fasb.org/extlink&oid=6525008 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The amount of decrease that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Target allocation of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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