Consolidated Statements of Comprehensive Income (Loss) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Statement [Abstract]
Net income (loss)	$ 279,804	$ 252,319	$ (185,344)
Other comprehensive income (loss):
Unrealized gain (loss) on derivative financial instruments	8,367	5,453	(6,964)
Gain on interest rate swaps not designated as cash flow hedges	2,481	5,038
Amortization of unrealized gains and losses on securities	(775)	(908)	(1,489)
Amortization of deferred gains and losses on settlement of swaps	(56)	(109)	(98)
Other-than-temporary impairments of securities related to fair value adjustments in excess of expected credit losses, net of amortization	688	(326)	(6,576)
Other comprehensive income (loss)	10,705	9,148	(15,127)
Comprehensive income (loss)	290,509	261,467	(200,471)
Comprehensive (income) loss attributable to noncontrolling interests	(98,790)	6,015
Comprehensive income (loss) attributable to Capital Trust, Inc.	$ 191,719	$ 267,482	$ (200,471)