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Defined Benefit Plan Target Allocation Percentage Of Assets Debt Securities Range Maximum1

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Defined Benefit Plan Target Allocation Percentage Of Assets Equity Securities Range Maximum 1

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Defined Benefit Plan Target Allocation Percentage Of Assets Equity Securities Range Minimum 1

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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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Target allocation maximum percentage 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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Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

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Reference 1: 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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-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

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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.

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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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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Pension Benefits - Schedule of Plan Assets Allocations (Detail) - Pension Benefits	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Plan Assets, Total		100.00%	100.00%	100.00%
Scenario, Forecast
Defined Benefit Plan Disclosure [Line Items]
Equity Securities, target allocation minimum	55.00%
Equity Securities, target allocation maximum	65.00%
Debt Securities, target allocation minimum	27.00%
Debt Securities, target allocation maximum	33.00%
Real Estate, target allocation minimum	8.00%
Real Estate, target allocation maximum	12.00%
Plan Assets, Total	100.00%
Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Plan Assets		57.00%	58.00%	60.00%
Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Plan Assets		33.00%	32.00%	30.00%
Real Estate
Defined Benefit Plan Disclosure [Line Items]
Plan Assets		10.00%	10.00%	10.00%