Basis of Condensed Consolidated Financial Statements (Cash, Cash Equivalents and Restricted Cash) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents	$ 82,042	$ 85,271	$ 85,031
Restricted cash included in other assets	11,662	9,967	9,756
Restricted cash included in prepaid expenses and other current assets	2,024	3,012	1,070
Total cash, cash equivalents and restricted cash	$ 95,728	$ 98,250	$ 95,857	$ 132,154