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Benefit Plans (Allocation of Plan Assets) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 188.9 | $ 322.3
Weighted average asset allocations | 100.00% | 100.00%
Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 188.3 | $ 321.3
Level 2 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.6 | 1.0
Cash [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.6 | 1.1
Cash [Member] | Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 0.6 | $ 1.1
Equity Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 62.00% | 63.00%
Target allocation | 65.00% |
Allocation range minimum | 60.00% |
Allocation range maximum | 70.00% |
Indexed Mutual Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 79.2 | $ 142.3
Indexed Mutual Funds [Member] | Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 79.2 | 142.3
International Mutual Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 37.7 | 58.7
International Mutual Funds [Member] | Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 37.7 | $ 58.7
Debt Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 35.00% | 35.00%
Target allocation | 35.00% |
Allocation range minimum | 30.00% |
Allocation range maximum | 40.00% |
Other [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 3.00% | 2.00%
Target allocation | 0.00% |
Allocation range minimum | 0.00% |
Allocation range maximum | 5.00% |
Mutual Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 63.0 | $ 111.4
Mutual Funds [Member] | Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 63.0 | 111.4
Insurance Contract [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.6 | 1.0
Insurance Contract [Member] | Level 2 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.6 | 1.0
Balanced Mutual Fund [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 7.8 | 7.8
Balanced Mutual Fund [Member] | Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 7.8 | $ 7.8

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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + 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=49178875&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=58740216&loc=d3e1928-114920 + Details
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