Employee Benefits Plans (Asset Allocation For The Defined Benefit Pension Plan As Of The Measurement Date, By Asset Category) (Detail)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Percentage of Plan Assets	100.00%	100.00%
Marketable Equity Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation 2013	68.00%
Allowable Allocation Range, Minimum	50.00%
Allowable Allocation Range, Maximum	80.00%
Percentage of Plan Assets	63.00%	61.00%
Debt Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation 2013	32.00%
Allowable Allocation Range, Minimum	20.00%
Allowable Allocation Range, Maximum	40.00%
Percentage of Plan Assets	32.00%	32.00%
Other [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation 2013	0.00%
Allowable Allocation Range, Minimum	3.00%
Allowable Allocation Range, Maximum	10.00%
Percentage of Plan Assets	5.00%	7.00%

Defined Benefit Plan Assets Target Allocations Total

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- Definition

Defined Benefit Plan Target Allocation Percentage Plan Assets

+ References

No definition available.

+ Details

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- Details

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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 1

-Subparagraph (d)(i)

-URI http://asc.fasb.org/extlink&oid=21915506&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=21915506&loc=d3e2446-114920

+ Details

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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

+ Details

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