Defined Benefit Plan, Actual Plan Assets Allocations, Number of Investments

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Defined US benefit plan pension benefit obligation US percentage

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- Definition

Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements, Net of Tax

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- Definition

Defined Benefit Plans, Number of Union Sponsored Multiemployer Plans

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- Definition

Retirement Benefits, Number Of Defined Benefit Pension Plans

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- Definition

Retirement Benefits, Number Of Defined Benefit Pension Plans Which Have Stopped Earning Benefits

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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- Definition

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-SubTopic 20
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This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

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- Definition

Amount of contributions made to multiemployer plan by all employers who participate in plan.

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-Publisher FASB
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-SubTopic 80
-Section 50
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Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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Employee Benefit Plans (Narrative) (Details) $ in Millions	1 Months Ended	12 Months Ended
Employee Benefit Plans (Narrative) (Details) $ in Millions	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) pension_plan investment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of significant plans \| pension_plan		3
Pension benefit obligation (as a percent)		86.00%
Number of frozen plans \| pension_plan		1
Cash surrender value	$ 2.5	$ 2.5	$ 2.5	$ 2.5
Target allocation (as a percent)	100.00%	100.00%	100.00%
Number of investments \| investment		7
Settlements of benefit obligation	$ 59.8	$ 0.0	$ 59.8	0.0
Defined benefit plan, recognized net loss due to settlements	15.3	0.0	$ 15.3	$ 0.0
Defined benefit plan, recognized net loss due to settlements, net of tax	$ 9.5
Expected employer contributions		$ 1.0
Number of union sponsored multiemployer plans \| pension_plan		2
Aggregate contributions		$ 0.8
Withdrawal obligation		$ 19.3
Equities
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as a percent)	55.00%	53.00%	55.00%
Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Number of investments \| investment		6
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Average rate used to determine discount rate		25.00%
Other Postretirement Benefits Plan \| Active Plans \| Bonds
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as a percent)		25.00%
Other Postretirement Benefits Plan \| Active Plans \| Equities
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as a percent)		75.00%
Other Postretirement Benefits Plan \| Frozen Plans \| Bonds
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as a percent)		60.00%
Other Postretirement Benefits Plan \| Frozen Plans \| Equities
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as a percent)		40.00%
Minimum \| U.S. treasuries
Defined Benefit Plan Disclosure [Line Items]
Maturities (term)		20 years
Maximum \| U.S. treasuries
Defined Benefit Plan Disclosure [Line Items]
Maturities (term)		30 years