Leases - Balance Sheet Information (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Leases [Abstract]
Operating lease right-of-use assets	$ 41,453	$ 35,436	$ 34,463
Operating - current	8,443	7,392	7,037
Operating - noncurrent	33,354	27,930	27,256
Total operating lease liabilities	41,797	35,322	34,293
Property and equipment, gross	3,569	3,569	3,569
Accumulated amortization	(3,036)	(2,739)	(2,578)
Property and equipment, net	533	830	991
Other current liabilities	771	1,125	1,116
Other long-term liabilities	0	386	764
Total finance lease liabilities	$ 771	$ 1,511	$ 1,880