Notes Payable - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Interest incurred and expensed
Interest expense on debt and capital lease obligations	$ 11,266	$ 11,328
Noncash interest on derivatives and capital lease obligations, net	(3,137)	(657)
Amortization of deferred financing fees	747	578
Total interest incurred and expensed on debt and capital lease obligations	$ 8,876	$ 11,249