Accumulated Other Comprehensive (Loss) Income - Schedule of Accumulated Other Comprehensive (loss) Income (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive (loss) income	$ (558)	$ 313	$ 496
Balance, beginning of year	313	496
Net unrealized (loss) gain	(103)	(39)	75
Net unrealized loss		(5)	(4)
Balance, end of year	(558)	313	496
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive (loss) income	(255)	454	629
Balance, beginning of year	454	629	547
Net unrealized (loss) gain	(681)	(133)	86
Repurchase of shares under normal course issuer bids [note 19]	(28)	(42)	(4)
Balance, end of year	(255)	454	629
Accumulated Net (Loss) Gain from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive (loss) income	(113)	(20)	34
Balance, beginning of year	(20)	34	(23)
Net unrealized (loss) gain	(103)	(39)	75
Reclassification of net loss (gain) to net income	10	(15)	(18)
Balance, end of year	(113)	(20)	34
Accumulated Net Unrealized Loss On Other Long Term Liabilities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive (loss) income	(186)	(117)	(168)
Balance, beginning of year	(117)	(168)	(107)
Net unrealized (loss) gain	(72)	44	(72)
Reclassification of net loss (gain) to net income	3	7	11
Balance, end of year	(186)	(117)	(168)
Accumulated Net Unrealized Investment (Loss) Gain [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total accumulated other comprehensive (loss) income	(4)	(4)	1
Balance, beginning of year	(4)	1	5
Net unrealized loss		(5)	(4)
Balance, end of year	$ (4)	$ (4)	$ 1

Other comprehensive income foreign currency translation adjustment repurchase of shares net of tax.

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Other comprehensive income net unrealized gain on other long term liabilities.

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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

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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

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- Definition

Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

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

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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