Income Taxes - Reconciliation from GAAP Net Loss to Taxable Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Income Tax Disclosure [Abstract]
GAAP net income (loss)	$ 42,428	$ (485)	$ (9,845)	$ 10,845	$ (8,557)	$ (2,306)	$ (7,619)	$ (1,168)	$ 42,943		$ (19,650)		$ (39,395)
Less: Taxable REIT subsidiary GAAP net income (loss)									10,235		6,154		46,896
GAAP net income (loss) from REIT operations									53,178	[1]	(13,496)	[1]	7,501	[1]
Depreciation and amortization									69,597		42,086		10,619
Gains and losses from capital transactions									(62,222)		776		(115,065)
Share-based compensation expense									7,821		2,569		205
Amortization of mortgage loan premium									(6,495)		(567)		32
Allowance for doubtful accounts									(295)		855		(480)
Vesting of restricted shares and dividends									(31)		(225)		(674)
Deferred revenue									(550)		1,458		(329)
Capitalizable acquisition costs									3,292		12,980		2,119
Straight line rent									(7,498)		(2,148)		(2,883)
Interest expense									(122)		0		(214)
Nontaxable dividend income									(3,189)		(1,732)		(3,707)
Prepaid revenue									(3,105)		4,557		0
Prepaid insurance									877		(955)		0
Other differences									245		(1,288)		829
Taxable income (loss) before adjustments (2)									51,503	[2]	44,870	[2]	(102,047)	[2]
Less: NOL carry forward									0		0		0
Adjusted taxable income subject to 90% dividend requirement									$ 51,503		$ 44,870		$ 0

[1] GAAP net income (loss) from REIT operations is net of amounts attributable to noncontrolling interests.

[2] An estimated taxable income (loss) before adjustments is presented. The Company plans to file its 2014 tax return with the IRS on or before the extended due date of September 15, 2015.