Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 44,981	$ 31,537	$ 78,090	$ 61,551
Other comprehensive income (loss):
Change in unrealized gains on securities	(42,354)	(1,723)	(39,540)	(839)
Less: reclassification adjustment for gains in net income	23,487	0	23,498	0
Increase (decrease) in fair value of cash flow hedge	1,837	(3,635)	7,811	(1,305)
Less: reclassification adjustment for amounts recognized in net income	509	(1,177)	2,017	(2,134)
Total other comprehensive income (loss)	(20,195)	735	(21,836)	(1,668)
Comprehensive income	24,786	32,272	56,254	59,883
Less: comprehensive income attributable to noncontrolling interest	(386)	(355)	(770)	(685)
Comprehensive income attributable to common stockholders	$ 24,400	$ 31,917	$ 55,484	$ 59,198