Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Provision at statutory rate									$ 28,892	$ 49,316	$ 24,393
Provision at statutory rate (as a percent)									35.00%	35.00%	35.00%
Non-taxable REIT income									$ (25,733)	$ (44,247)	$ (26,215)
Non-taxable REIT income (as a percent)									(31.20%)	(31.40%)	(37.60%)
State and local tax provision									$ 1,284	$ 2,420	$ 348
State and local tax provision (as a percent)									1.60%	1.70%	0.50%
Other									$ 24,047	$ (1,227)	$ (853)
Other (as a percent)									29.10%	(0.90%)	(1.20%)
Valuation allowance									$ (23,955)	$ 133	$ 3,066
Valuation allowance (as a percent)									(29.00%)	0.10%	4.40%
Total provision	$ 64	$ 3,048	$ 1,178	$ 245	$ 1,727	$ 1,100	$ 538	$ 3,030	$ 4,535	$ 6,395	$ 739
Total provision (as a percent)									5.50%	4.50%	1.10%