Debt Obligations, net (Future Scheduled Maturities) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Aggregate amounts of principal maturities of long-term debt
2012 (remaining nine months)	$ 469,166	[1]
2013	1,908,150	[1]
2014	1,582,601	[1]
2015	187,765	[1]
2016	384,403	[1]
Thereafter	1,129,879	[1]
Total principal maturities	5,661,964	[1]	5,874,183
Unamortized debt discounts, net	(58,025)	[1],[2]	(36,643)	[2]
Total long-term debt obligations, net	5,603,939	[1]	5,837,540
Unsecured debt
Aggregate amounts of principal maturities of long-term debt
2012 (remaining nine months)	469,166	[1]
2013	1,017,209	[1]
2014	200,601	[1]
2015	105,765	[1]
2016	261,403	[1]
Thereafter	474,722	[1]
Total principal maturities	2,528,866	[1]
Unamortized debt discounts, net	(23,826)	[1]
Total long-term debt obligations, net	2,505,040	[1]
Secured Debt
Aggregate amounts of principal maturities of long-term debt
2012 (remaining nine months)	0	[1]
2013	890,941	[1]
2014	1,382,000	[1]
2015	82,000	[1]
2016	123,000	[1]
Thereafter	655,157	[1]
Total principal maturities	3,133,098	[1]
Unamortized debt discounts, net	(34,199)	[1]
Total long-term debt obligations, net	$ 3,098,899	[1]

[1] All of the Company's non-accrual loans are considered impaired and included in the table above. In addition, as of June 30, 2012 and December 31, 2011, certain loans modified through troubled debt restructurings with a recorded investment of $205.5 million and $255.3 million, respectively, are also included as impaired loans in accordance with GAAP although they are performing and on accrual status.

[2] The Company's convertible senior floating rate notes due October 2012 ("Convertible Notes") are convertible at the option of the holders into 22.2 shares per $1,000 principal amount of Convertible Notes (reflecting a conversion price of $45.05), on or after August 15, 2012, or prior to that date if certain conditions are met. None of the conversion conditions have been met as of June 30, 2012. As of June 30, 2012, the unamortized discount on these notes was $2.5 million, the net carrying amount of the liability was $466.7 million and the carrying value of the additional paid-in-capital, or equity component of the convertible notes was $34.7 million. For the three and six months ended June 30, 2012, the Company recognized interest expense on the convertible notes of $3.1 million and $8.3 million, respectively, of which $1.8 million and $4.8 million, respectively, related to the amortization of the debt discount. For the three and six months ended June 30, 2011, the Company recognized interest expense on the convertible notes of $4.5 million and $8.9 million respectively, of which $2.9 million and $5.7 million, respectively, related to the amortization of the debt discount.