Equity - Schedule of Primary Components of Accumulated Other Comprehensive Loss (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning			$ 798
Consolidation of additional securitization vehicles		(4,360)
Amortization of net deferred gains on settlement of swaps	(56)	(109)
Deconsolidation of subsidiaries	29,889
Balance, ending			798
Mark-to-Market on Interest Rate Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning	(27,423)	(37,914)
Unrealized gain on derivative financial instruments	8,367	5,453
Ineffective portion of cash flow hedges	2,481	5,038
Deconsolidation of subsidiaries	16,575
Balance, ending		(27,423)
Deferred Gains on Settled Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning	56	165
Amortization of net deferred gains on settlement of swaps	(56)	(109)
Balance, ending		56
Other- Than-Temporary Impairments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning	(16,578)	(16,800)
Consolidation of additional securitization vehicles		538
Other-than-temporary impairments of securities	678	(326)
Allocation to non-controlling interest		10
Deconsolidation of subsidiaries	15,900
Balance, ending		(16,578)
Unrealized Gains on Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning	3,361	4,087
Amortization of net unrealized gains on securities	(775)	(908)
Allocation to non-controlling interest		182
Deconsolidation of subsidiaries	(2,586)
Balance, ending		3,361
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning	(40,584)	(50,462)
Consolidation of additional securitization vehicles		538
Unrealized gain on derivative financial instruments	8,367	5,453
Ineffective portion of cash flow hedges	2,481	5,038
Amortization of net unrealized gains on securities	(775)	(908)
Amortization of net deferred gains on settlement of swaps	(56)	(109)
Other-than-temporary impairments of securities	678	(326)
Allocation to non-controlling interest		192
Deconsolidation of subsidiaries	29,889
Balance, ending		$ (40,584)