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Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Total accumulated other comprehensive loss | $ (558) | $ (558)
Balance, beginning of year | (558) |
Net unrealized loss | (244) | (103)
Balance, end of year | (1,470) | (558)
Accumulated Translation Adjustment [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Total accumulated other comprehensive loss | (255) | 454
Balance, beginning of year | (255) | 454
Net unrealized loss | (798) | (681)
Repurchase of shares under normal course issuer bids [note 21] | 11 | (28)
Balance, end of year | (1,042) | (255)
Accumulated Net (Loss) Gain from Designated or Qualifying Cash Flow Hedges [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Total accumulated other comprehensive loss | (113) | (20)
Balance, beginning of year | (113) | (20)
Net unrealized loss | (244) | (103)
Reclassification of net loss to net income | 95 | 10
Balance, end of year | (262) | (113)
Accumulated Net Unrealized Loss On Other Long Term Liabilities [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Total accumulated other comprehensive loss | (186) | (117)
Balance, beginning of year | (186) | (117)
Net unrealized gain (loss) | 14 | (72)
Reclassification of net loss to net income | 7 | 3
Balance, end of year | (165) | (186)
Accumulated Net Unrealized Loss on Available-for-Sale investments [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Total accumulated other comprehensive loss | (4) | (4)
Balance, beginning of year | (4) | (4)
Net unrealized loss | 3 |
Balance, end of year | $ (1) | $ (4)

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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 + Details
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- Definition Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 20 -Subparagraph (b,c) -URI http://asc.fasb.org/extlink&oid=6915805&loc=d3e32211-110900 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 + Details
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