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Income Taxes - Summary of Changes in Gross Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014
Income Tax Disclosure [Abstract] |  |
Balance, beginning of year | $ 202 | $ 238
Increase based on tax positions related to current year | 17 | 21
Increase (decrease) based on tax positions of prior years | 53 | (23)
Settlements | (15) | (8)
Statute expirations | (20) | (10)
Foreign currency translation | (16) | (16)
Balance, ending of year | $ 221 | $ 202

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- Definition Unrecognized tax benefits increase decrease resulting from foreign currency translation. + References No definition available. + Details
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- Definition Unrecognized tax benefits increase decreases resulting from prior period tax positions. + References No definition available. + Details
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- Definition Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns. + 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 (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Unrecognized Tax Benefit -URI http://asc.fasb.org/extlink&oid=6527854 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. + 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. + 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. + 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 (a)(4) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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