Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities
Net income	$ 100,494	$ 25,424	$ 279,804
Adjustments to reconcile net income to net cash provided by operating activities
Recovery of provision for loan losses			(36,147)
Valuation allowance on loans held-for-sale	(1,300)	(1,259)
Unrealized gain on investments at fair value	(13,258)	(7,417)	(51,904)
Income from equity investments in unconsolidated subsidiaries	(28,036)		(1,781)
Loss (gain) on deconsolidation of subsidiary	8,615		(200,283)
Other non-cash income (loss)		(38)	(5,896)
Non-cash compensation expense	9,716	6,242	3,808
Distributions of income from unconsolidated subsidiaries	17,867	8,795	1,933
Distributions from CT Legacy Asset			9,581
Loss on sale of discontinued operations			271
Amortization of deferred interest on loans	(19,785)	(6,290)	(566)
Amortization of deferred financing costs and premiums/discount on debt obligations	9,900	4,935	12,133
Changes in assets and liabilities, net
Accrued interest receivable, prepaid expenses, and other assets	(13,166)	116	(1,751)
Accounts payable, accrued expenses, and other liabilities	8,290	(1,839)	(2,434)
Net cash provided by operating activities	80,637	28,669	6,768
Cash flows from investing activities
Proceeds from Investment Management Business Sale			21,424
Origination and fundings of loans receivable	(3,067,263)	(2,327,913)
Origination and exit fees received on loans receivable	35,449	25,402
Principal collections and proceeds from the sale of loans receivable and other assets	620,413	508,718	172,462
Distributions from equity investments		7,151
Contributions to unconsolidated subsidiaries			(4,030)
Distributions from unconsolidated subsidiaries			1,006
(Increase) decrease in restricted cash	(1,495)	4,151	(1,261)
Net cash (used in) provided by investing activities	(2,412,896)	(1,782,491)	189,601
Cash flows from financing activities
Repayment and purchase of secured notes		(11,059)
Borrowings under revolving repurchase facilities	2,898,427	1,356,796	123,977
Repayments under revolving repurchase facilities	(1,709,740)	(571,380)	(58,464)
Borrowings under asset-specific repurchase agreements	298,512	310,827
Repayments under asset-specific repurchase agreements	(216,904)	(7,104)
Proceeds from issuance of convertible notes		168,415
Repayment of other liabilities	(20,794)	(98,965)	(241,945)
Proceeds from sale of loan participations	494,306	90,000
Repayment of loan participations	(61,836)
Payment of deferred financing costs	(16,160)	(8,867)
Settlement of interest rate swaps		(6,123)
Contributions from non-controlling interests		15,000
Purchase of and distributions to non-controlling interests	(13,775)	(72,853)	(16)
Proceeds from issuance of common stock	766,138	633,807	10,000
Dividends paid on class A common stock	(84,238)	(7,776)	(48,960)
Vesting of restricted class A common stock			(356)
Net cash provided by (used in) financing activities	2,333,936	1,790,718	(215,764)
Net increase (decrease) in cash and cash equivalents	1,677	36,896	(19,395)
Cash and cash equivalents at beginning of year	52,342	15,423	34,818
Effects of currency translation on cash and cash equivalents	(2,209)	23
Cash and cash equivalents at end of year	51,810	52,342	15,423
Supplemental disclosure of cash flows information
Payments of interest	(55,174)	(12,702)	(26,363)
(Payments) receipts of income taxes	(1,473)	8	(2,747)
Supplemental disclosure of non-cash investing and financing activities
Dividends declared, not paid	30,357	13,302	804
Participations sold, net	432,470	90,000
Deconsolidation (consolidation) of subsidiaries	$ 8,615	$ (38,913)	$ 371,621