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Retirement Plans and Postretirement Benefit Plans Postretirement Benefit Plans (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2018
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Employer contributions |  | $ 20.0 | $ 15.0 |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |
Level 3 Asset Value, Beginning of Period |  | 36.0 |  |  |  |  |  |
Interest income |  | 0.8 |  |  |  |  |  |
Dividend income |  | 0.5 |  |  |  |  |  |
Unrealized gains |  | 1.4 |  |  |  |  |  |
Administrative expenses and charges |  | (0.1) |  |  |  |  |  |
Claims paid |  | (3.8) |  |  |  |  |  |
Level 3 Asset Value, End of Period |  | 34.8 | 36.0 |  |  |  |  |
Postretirement Plan, Expected Future Benefit Payments, Next Twelve Months |  |  |  |  | $ 11.2 |  |  |
Postretirement Plan, Expected Future Benefit Payments, Year Two |  |  |  |  | 11.2 |  |  |
Postretirement Plan, Expected Future Benefit Payments, Year Three |  |  |  |  | 11.1 |  |  |
Postretirement Plan, Expected Future Benefit Payments in Year Four |  |  |  |  | 9.5 |  |  |
Postretirement Plan, Expected Future Benefit Payments, Year Five |  |  |  |  | 9.4 |  |  |
Postretirement Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter |  |  |  |  | 42.3 |  |  |
Postemployment Benefits Liability |  |  |  |  | 2.1 |  | $ 1.9 |
Defined Contribution Plan, Cost |  | $ 14.4 | 13.2 | $ 13.2 |  |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  | 5.00% |  |  |  |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  | 200.00% |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value |  | $ 34.8 | 36.0 |  | 34.8 |  | 36.0 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Claims Paid |  | 3.8 |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Administrative Expenses and Charges |  | 0.1 |  |  |  |  |  |
Unrealized gains |  | 1.4 |  |  |  |  |  |
Interest income |  | 0.8 |  |  |  |  |  |
Dividend income |  | 0.5 |  |  |  |  |  |
Cash [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 0.9 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  |  | 0.9 |  |  |  |  |
Fair Value, Inputs, Level 1 [Member] | Cash [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 0.9 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  |  | 0.9 |  |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Cash [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 |  |  |  |  |
Pension Plan [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |  |  |  |  |
Benefit Obligation, Beginning |  | 615.9 | 687.5 |  |  |  |  |
Service cost |  | 12.9 | 14.9 | 15.5 |  |  |  |
Interest cost |  | 20.7 | 23.8 | 26.2 |  |  |  |
Plan settlements |  | (83.1) | (73.7) |  |  |  |  |
Actuarial losses (gains) |  | 64.3 | (22.0) |  |  |  |  |
Benefit Obligation, Ending |  | 616.1 | 615.9 | 687.5 |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 522.8 | 635.3 |  |  |  |  |
Actual return on plans' assets |  | 85.2 | (39.2) |  |  |  |  |
Employer contributions |  | 20.0 | 15.0 |  |  |  |  |
Plan settlements |  | (83.1) | (73.7) |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 530.3 | 522.8 | 635.3 |  |  |  |
Funded Status of Plan |  |  |  |  | $ (85.8) |  | $ (93.1) |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |
Service cost |  | 12.9 | 14.9 | 15.5 |  |  |  |
Interest cost |  | 20.7 | 23.8 | 26.2 |  |  |  |
Expected return on plan assets |  | (36.1) | (44.1) | (42.6) |  |  |  |
Amortization of unrecognized prior service cost | [1] | 0.0 | 0.0 | (0.1) |  |  |  |
Settlement cost |  | 27.6 | 25.1 | 15.3 |  |  |  |
Net periodic benefit cost |  | 42.4 | 35.9 | 31.7 |  |  |  |
Amount paid by unconsolidated affiliates |  | 2.9 | 2.5 | 4.3 |  |  |  |
Net Periodic Benefit Cost, Net of Unconsolidated Affiliates |  | 39.5 | 33.4 | 27.4 |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |
Capitalized Portion of Net Periodic Benefit Cost |  | $ 3.6 | $ 3.8 | $ 4.4 |  |  |  |
Assumptions Used Calculating Benefit Obligation, Discount Rate |  |  |  | 3.60% | 3.15% |  | 4.20% |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate |  | 3.63% | 3.73% | 4.00% |  |  |  |
Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets |  | 7.50% | 7.50% | 7.50% |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase |  |  |  | 4.20% | 4.20% |  | 4.20% |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase |  | 4.20% | 4.20% | 4.20% |  |  |  |
Defined Benefit Plan, Benefit Obligation, Benefits Paid |  | $ (14.6) | $ (14.6) |  |  |  |  |
Defined Benefit Plan, Plan Assets, Benefits Paid |  | 14.6 | 14.6 |  |  |  |  |
Accumulated Benefit Obligation |  |  |  |  | $ 563.3 |  | $ 561.9 |
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment |  | 0.0 | 0.0 |  |  |  |  |
Pension Plan [Member] | Equity Funds [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [2] | 19.7 |  |  |  |  |  |
Fair Value of Plan Assets, Ending | [2] | 23.9 | 19.7 |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |
Alternative Investment |  |  |  |  | 23.9 | [3],[4] | 19.7 | [2],[5]
Pension Plan [Member] | Money market funds [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 |  | 7.5 | 0.3 |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |
Alternative Investment |  |  |  |  | 7.5 | [3] | 0.3 | [5]
Pension Plan [Member] | Fair Value, Inputs, Level 1 [Member] | Equity Funds [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [2] | 0.0 |  |  |  |  |  |
Fair Value of Plan Assets, Ending | [2] | 0.0 | 0.0 |  |  |  |  |
Pension Plan [Member] | Fair Value, Inputs, Level 1 [Member] | Money market funds [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 |  |  |  |  |
Pension Plan [Member] | Fair Value, Inputs, Level 2 [Member] | Equity Funds [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning | [2] | 0.0 |  |  |  |  |  |
Fair Value of Plan Assets, Ending | [2] | 0.0 | 0.0 |  |  |  |  |
Pension Plan [Member] | Fair Value, Inputs, Level 2 [Member] | Money market funds [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 |  |  |  |  |
Pension Plan [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 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |  |  |  |  |
Benefit Obligation, Beginning |  | 135.8 | 149.4 |  |  |  |  |
Service cost |  | 0.2 | 0.3 | $ 0.6 |  |  |  |
Interest cost |  | 5.6 | 5.4 | 7.2 |  |  |  |
Plan settlements |  | 0.0 | 0.0 |  |  |  |  |
Actuarial losses (gains) |  | 2.9 | (9.6) |  |  |  |  |
Benefit Obligation, Ending |  | 136.5 | 135.8 | 149.4 |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 45.3 | 50.2 |  |  |  |  |
Actual return on plans' assets |  | 4.6 | (0.6) |  |  |  |  |
Employer contributions |  | 5.1 | 5.4 |  |  |  |  |
Plan settlements |  | 0.0 | 0.0 |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 47.0 | 45.3 | 50.2 |  |  |  |
Funded Status of Plan |  |  |  |  | $ (89.5) |  | $ (90.5) |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |
Service cost |  | 0.2 | 0.3 | 0.6 |  |  |  |
Interest cost |  | 5.6 | 5.4 | 7.2 |  |  |  |
Expected return on plan assets |  | (1.9) | (2.0) | (2.2) |  |  |  |
Amortization of unrecognized prior service cost | [1] | (8.4) | (8.4) | (3.5) |  |  |  |
Settlement cost |  | 0.0 | 0.0 | 0.6 |  |  |  |
Net periodic benefit cost |  | (2.5) | (0.9) | 4.7 |  |  |  |
Amount paid by unconsolidated affiliates |  | (0.6) | (0.5) | 0.3 |  |  |  |
Net Periodic Benefit Cost, Net of Unconsolidated Affiliates |  | (1.9) | (0.4) | 4.4 |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |
Capitalized Portion of Net Periodic Benefit Cost |  | $ 0.2 | $ 0.2 | $ 1.2 |  |  |  |
Assumptions Used Calculating Benefit Obligation, Discount Rate |  |  |  | 3.70% | 3.25% |  | 4.30% |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate |  | 4.30% | 3.70% | 4.20% |  |  |  |
Health Care Cost Trend Rate Assumed for Next Fiscal Year |  |  |  |  |  |  | 7.00% |
Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets |  | 4.00% | 4.00% | 4.00% |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase |  |  |  | 4.20% |  |  |  |
Defined Benefit Plan, Benefit Obligation, Benefits Paid |  | $ (12.1) | $ (13.5) |  |  |  |  |
Defined Benefit Plan, Plan Assets, Benefits Paid |  | 12.1 | 13.5 |  |  |  |  |
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment |  | 0.0 | 0.0 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Group Retiree Medical Insurance Contract [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 36.0 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 34.8 | 36.0 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | U.S. Equity Mutual Funds Investment [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 8.9 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 10.9 | 8.9 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Money market funds [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 1.2 |  |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [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 |  | 9.8 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 12.1 | 9.8 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member] | Group Retiree Medical Insurance Contract [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 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Equity Mutual Funds Investment [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 8.9 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 10.9 | 8.9 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member] | Money market funds [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 1.2 |  |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [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 |  |  |  |  |
Other Postretirement Benefit 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 |  | 36.0 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 34.8 | 36.0 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member] | Group Retiree Medical Insurance Contract [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 36.0 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 34.8 | 36.0 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Equity Mutual Funds Investment [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 |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member] | Money market funds [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 0.0 |  |  |  |  |  |
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |  |  |  |  |
Fair Value of Plan Assets, Beginning |  | 45.8 |  |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 46.9 | 45.8 |  |  |  |  |
Other Pension Plan [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |  |  |  |  |
Benefit Obligation, Beginning |  | 9.6 | 8.1 |  |  |  |  |
Service cost |  | 0.5 | 0.4 | $ 0.3 |  |  |  |
Interest cost |  | 0.4 | 0.3 | 0.3 |  |  |  |
Plan settlements |  | (1.2) | (2.0) |  |  |  |  |
Actuarial losses (gains) |  | 0.7 | 2.8 |  |  |  |  |
Benefit Obligation, Ending |  | 10.3 | 9.6 | 8.1 |  |  |  |
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 |  | 1.2 | 2.0 |  |  |  |  |
Plan settlements |  | (1.2) | (2.0) |  |  |  |  |
Fair Value of Plan Assets, Ending |  | 0.0 | 0.0 | 0.0 |  |  |  |
Funded Status of Plan |  |  |  |  | $ (10.3) |  | $ (9.6) |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |
Service cost |  | 0.5 | 0.4 | 0.3 |  |  |  |
Interest cost |  | 0.4 | 0.3 | 0.3 |  |  |  |
Expected return on plan assets |  | 0.0 | 0.0 | 0.0 |  |  |  |
Amortization of unrecognized prior service cost | [1] | 0.0 | 0.1 | 0.1 |  |  |  |
Settlement cost |  | 0.5 | 1.0 | 0.0 |  |  |  |
Net periodic benefit cost |  | 1.9 | 2.5 | 1.1 |  |  |  |
Amount paid by unconsolidated affiliates |  | 0.1 | 0.1 | 0.0 |  |  |  |
Net Periodic Benefit Cost, Net of Unconsolidated Affiliates |  | 1.8 | 2.4 | 1.1 |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |
Defined Benefit Plan, Benefit Obligation, Benefits Paid |  | 0.0 | 0.0 |  |  |  |  |
Defined Benefit Plan, Plan Assets, Benefits Paid |  | 0.0 | 0.0 |  |  |  |  |
Accumulated Benefit Obligation |  |  |  |  | $ 8.1 |  | $ 7.8 |
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment |  | 0.3 | 0.0 |  |  |  |  |
OKLAHOMA | Pension Plan [Member] |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |
Settlement cost | [6] | $ 17.9 | $ 22.1 | $ 13.2 |  |  |  |
[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] | This category represents units of participation in a commingled fund that primarily invested in stocks of international companies and emerging markets.
[3] | GAAP allows the measurement of certain investments that do not have a readily determinable fair value at the net asset value. These investments do not consider the observability of inputs; therefore, they are not included within the fair value hierarchy.
[4] | This category represents units of participation in a commingled fund that primarily invested in stocks of international companies and emerging markets.
[5] | GAAP allows the measurement of certain investments that do not have a readily determinable fair value at the net asset value. These investments do not consider the observability of inputs; therefore, they are not included within the fair value hierarchy.
[6] | Included in the pension regulatory asset or liability in each jurisdiction, as indicated in the regulatory assets and liabilities table in Note 1.

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- Definition Defined Benefit Plan, Net Periodic Benefit Cost, Net of Unconsolidated Affiliates + References No definition available. + Details
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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Administrative Expenses and Charges + References No definition available. + Details
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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Claims Paid + References No definition available. + Details
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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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