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.

No definition available.

+ 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=58740216&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=58740216&loc=d3e1928-114920

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ 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)
-URI http://asc.fasb.org/extlink&oid=58740216&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)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Details

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- Details

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- Details

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Retirement and Postretirement Plans - Asset Allocation of Plan Assets (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations (percentage)		100.00%	100.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations (percentage)		58.00%	59.00%
Fixed Income Securities Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations (percentage)		41.00%	40.00%
Other Defined Benefit Plan Category [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations (percentage)		1.00%	1.00%
Scenario, Forecast [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation range (percentage)	60.00%
Scenario, Forecast [Member] \| Fixed Income Securities Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation range (percentage)	40.00%