Compensation - Activity Associated with Limited Partnership Units (Detail) (Limited Partnership Units [Member])	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Limited Partnership Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance outstanding at beginning of period	68,480,097	45,814,354	40,851,365
Granted	49,577,157	41,691,703	21,244,357
Redeemed/exchanged units	(88,181,354)	(17,478,541)	(11,165,346)
Forfeited units		(1,547,419)	(5,116,022)
Balance outstanding at end of period	29,875,900	68,480,097	45,814,354

Number of exchangeable limited partnership units redeemed or exchanged into the Company's class A common stock during the period.

No definition available.

+ Details

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- Details

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- Definition

Number of shares under non-option equity instrument agreements that were either cancelled or expired.

+ References

+ Details

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- Definition

Net number of non-option equity instruments granted to participants.

+ References

+ Details

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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