Notes Payable - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Interest incurred and expensed
Interest expense on debt and capital lease obligations	$ 11,499	$ 12,541	$ 22,827	$ 25,594
Loss on derivatives, net	1,006	2,782	349	9,184
Amortization of deferred financing fees	579	549	1,157	1,104
Total interest incurred and expensed on debt and capital lease obligations	$ 13,084	$ 15,872	$ 24,333	$ 35,882