Equity Investments in Unconsolidated Subsidiaries - Activity Relating to Our Equity Investments in Unconsolidated Subsidiaries (Detail) (USD $) In Thousands, unless otherwise specified			9 Months Ended
Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 CTOPI Carried Interest [Member]
Schedule of Equity Method Investments [Line Items]
Beginning Balance	$ 25,632	$ 13,306	$ 13,306
Incentive income allocation			12,326
Ending Balance	$ 25,632	$ 13,306	$ 25,632

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant