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Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2013
Income Tax Disclosure [Abstract]
Unrecognized tax benefits, interest and penalties			$ 12.4
Unremitted Earnings	$ 717	$ 665

X

- Definition

Unremitted earning of foreign subsidiary.

+ References

No definition available.

+ Details

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- Details

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X

- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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