Employee Benefit Plans (Weighted Average Target Pension Plan Asset Allocations) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Asset Category
Gain (Loss) on Sale of Other Investments	$ 3.0	$ 3.0	$ 3.0
Equity Securities
Asset Category
Weighted average target pension plan asset allocation, minimum	30.00%	30.00%
Weighted average target pension plan asset allocation, maximum	65.00%	65.00%
Debt Securities
Asset Category
Weighted average target pension plan asset allocation, minimum	30.00%	30.00%
Weighted average target pension plan asset allocation, maximum	65.00%	65.00%
Real Estate
Asset Category
Weighted average target pension plan asset allocation, minimum	0.00%	0.00%
Weighted average target pension plan asset allocation, maximum	10.00%	10.00%
Other
Asset Category
Weighted average target pension plan asset allocation, minimum	0.00%	0.00%
Weighted average target pension plan asset allocation, maximum	10.00%	10.00%

No definition available.

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- Definition

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=35743120&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=35743120&loc=d3e1928-114920

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- Definition

Target allocation minimum 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 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: 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=35743120&loc=d3e2446-114920

+ Details

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- Definition

The difference between the book value and the sale price of other nonspecific investments. This element is used when other, more specific, elements are not appropriate. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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