Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Leases
Operating lease cost	$ 6,127	$ 18,524
Short-term lease cost	1,754	5,289
Variable lease cost	1,224	2,091
Total lease cost	9,105	25,904
Cash paid for amounts included in the measurement of lease liability operating cash flows	14,011	22,464
ROU assets obtained in exchange for lease liabilities	$ 253	$ 4,610
Weighted-average remaining lease term (in years)	19 years 7 months 13 days	19 years 7 months 13 days
Weighted-average discount rate	6.91%	6.91%