Defined Benefit Plan, Maximum Annual Employer Contributions, Amount

No definition available.

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- Definition

Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of payment for other postretirement benefits. Excludes pension benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

+ Details

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Period Type:	duration

- References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Employee Benefits, Defined Benefit Plans Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
VEBA Postretirement Medical Obligations
Payment for Other Postretirement Benefits	$ 15.7	$ 20.0
Fair Value, Inputs, Level 2 \| Fair Value, Measurements, Recurring [Member]
VEBA Postretirement Medical Obligations
Fair value of deferred compensation assets	9.9		$ 9.8
Voluntary Employees' beneficiary Association (VEBA) \| Union VEBA
VEBA Postretirement Medical Obligations
Maximum contribution threshold	12.8
Voluntary Employees' beneficiary Association (VEBA) \| Salaried VEBA
VEBA Postretirement Medical Obligations
Maximum contribution threshold	2.9
Payment for Other Postretirement Benefits	$ 2.9