Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

No definition available.

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- Definition

Cumulative adjustment resulting from gains and losses on foreign currency derivatives that are designated as, and are effective as, hedges of a net investment in a foreign entity, commencing as of the designation date. Adjustment reported in equity as part of accumulated other comprehensive income.

+ 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

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Financial Instruments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Cost-method Investments [Line Items]
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	$ 8
Foreign Exchange Forward [Member]
Schedule of Cost-method Investments [Line Items]
Derivatives used in Net Investment Hedge, Net of Tax		46	11
Interest Rate Swap [Member]
Schedule of Cost-method Investments [Line Items]
Derivative, Notional Amount		1,592	0
Interest Rate Caps [Member]
Schedule of Cost-method Investments [Line Items]
Derivative, Notional Amount		8,333	0
Interest Rate Caps [Member] \| Interest Rate Caps Sold
Schedule of Cost-method Investments [Line Items]
Derivative, Notional Amount		6,200	7,100
Interest Rate Caps [Member] \| Interest Rate Caps Purchased
Schedule of Cost-method Investments [Line Items]
Derivative, Notional Amount		2,100	1,800
Interest Rate Caps [Member] \| Interest Rate Caps Purchased \| Subsidiary Issuers
Schedule of Cost-method Investments [Line Items]
Derivative, Notional Amount		4,200	5,200
Currency Swap [Member]
Schedule of Cost-method Investments [Line Items]
Derivative, Notional Amount		$ 493	$ 0