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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 |

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- Definition Unremitted earning of foreign subsidiary. + References No definition available. + Details
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- 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 + Details
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