Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 41,786	$ 61,365	$ 29,804
Restricted cash	3,213	153	1,832
Current assets of discontinued operations	89	155	889
Restricted cash, less current portion	0		1,896
Cash, cash equivalents and restricted cash	45,088		$ 34,421
Discontinued Operations, Disposed of by Sale | WD Services
Cash and Cash Equivalents [Line Items]
Current assets of discontinued operations	$ 89	$ 155