Summary of Significant Accounting Policies (Deferred Financing Costs, Net of Accumulated Amortization) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Deferred financing costs	$ 11,488	$ 11,530
Accumulated amortization	(4,812)	(3,859)
Deferred financing costs, net	6,676	7,671
Fixed debt arrangements
Deferred financing costs	14,608	14,501
Accumulated amortization	(3,947)	(2,944)
Deferred financing costs, net	$ 10,661	$ 11,557