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Income Taxes - Schedule of Changes in Valuation Allowance (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Income Tax Disclosure [Abstract] |  |  |
Balance at beginning of year | $ 1,400 | $ 1,398 | $ 1,268
Increase to allowance | 471 | 45 | 157
Release of allowance | (41) | (31) | (31)
U.S. state tax apportionment and tax rate changes | (32) | (17) | 6
Foreign currency translation | 6 | 5 | (2)
Balance at end of year | $ 1,804 | $ 1,400 | $ 1,398

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- Definition Change in valuation allowance related to deferred state income taxes. + References No definition available. + Details
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- Definition Deferred tax assets valuation foreign currency translation. + References No definition available. + Details
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- Definition Deferred tax assets valuation release of allowance. + References No definition available. + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 + Details
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- Details
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- Definition The amount of the change in the period in the valuation allowance for a specified deferred tax asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=21917399&loc=d3e32123-109318 + Details
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