Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Investments in mortgages and loans, at amortized cost:
Commercial mortgages, mezzanine loans, other loans and preferred equity interests	$ 1,124,044	$ 1,075,129
Allowance for losses	(26,206)	(30,400)
Total investments in mortgages and loans	1,097,838	1,044,729
Investments in real estate, net of accumulated depreciation of $104,828 and $97,392, respectively	914,919	918,189
Investments in securities and security-related receivables, at fair value	670,245	655,509
Cash and cash equivalents	63,854	100,041
Restricted cash	88,397	90,641
Accrued interest receivable	49,558	47,335
Other assets	48,184	45,459
Deferred financing costs, net of accumulated amortization of $15,926 and $15,811, respectively	18,834	19,734
Intangible assets, net of accumulated amortization of $2,745 and $2,976, respectively	1,784	2,343
Total assets	2,953,613	2,923,980
Liabilities and Equity
Indebtedness ($293,623 and $216,703 at fair value, respectively)	1,888,850	1,799,595
Accrued interest payable	27,051	24,129
Accounts payable and accrued expenses	22,056	22,990
Derivative liabilities	141,518	151,438
Deferred taxes, borrowers' escrows and other liabilities	53,831	35,704
Total liabilities	2,133,306	2,033,856
Series D cumulative redeemable preferred shares, $0.01 par value per share, 4,000,000 shares authorized, 2,600,000 shares issued and outstanding	51,369	52,278
Shareholders' equity:
Common shares, $0.03 par value per share, 200,000,000 shares authorized, 60,758,957 and 58,913,142 issued and outstanding, including 383,384 unvested restricted common share awards at March 31, 2013	1,823	1,760
Additional paid in capital	1,859,449	1,837,389
Accumulated other comprehensive income (loss)	(87,419)	(95,173)
Retained earnings (deficit)	(1,008,952)	(910,086)
Total shareholders' equity	764,978	833,961
Noncontrolling interests	3,960	3,885
Total equity	768,938	837,846
Total liabilities and equity	2,953,613	2,923,980
7.75% Series A cumulative redeemable preferred shares
Shareholders' equity:
Preferred shares, $0.01 par value per share, 25,000,000 shares authorized	37	31
8.375% Series B cumulative redeemable preferred shares
Shareholders' equity:
Preferred shares, $0.01 par value per share, 25,000,000 shares authorized	23	23
8.875% Series C cumulative redeemable preferred shares
Shareholders' equity:
Preferred shares, $0.01 par value per share, 25,000,000 shares authorized	17	17
Series E cumulative redeemable preferred shares
Shareholders' equity:
Preferred shares, $0.01 par value per share, 25,000,000 shares authorized	$ 0	$ 0