Leases - Balance Sheet Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Operating Lease
Operating lease right-of-use assets	$ 88,753	$ 88,753
Operating lease liabilities - Current	23,516	23,516
Operating lease liabilities - Non-current	76,080	76,080
Total operating lease liabilities	99,596	99,596
Finance Lease
Property and equipment, gross	1,755	1,755	$ 1,459
Accumulated depreciation	(1,112)	(1,112)	(1,001)
Property and equipment, net	643	643	458
Finance lease liabilities - Current	248	248	223
Finance lease liabilities - Non-current	436	436	$ 315
Total finance lease liabilities	684	684
Operating lease, impairment charge	$ 0	$ 989