Leases - Balance Sheet Information (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Leases [Abstract]
Operating lease right-of-use assets	$ 36,930	$ 35,436	$ 35,111
Operating - current	8,099	7,392	6,647
Operating - noncurrent	28,893	27,930	28,164
Total operating lease liabilities	36,992	35,322	34,811
Property and equipment, gross	3,569	3,569	3,569
Accumulated amortization	(2,953)	(2,739)	(2,417)
Property and equipment, net	616	830	1,152
Other current liabilities	998	1,125	1,107
Other long-term liabilities	0	386	1,047
Total finance lease liabilities	$ 998	$ 1,511	$ 2,154