Commitments and Contingencies - Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Future minimum lease payments under noncancellable operating leases - As Lessor
Remainder of 2019	$ 15,329		$ 15,329
2020	29,840		29,840
2021	26,507		26,507
2022	17,342		17,342
2023	13,278		13,278
2024 and thereafter	21,653		21,653
Total future minimum lease payments	123,949		123,949
Future minimum lease payments under noncancelable operating leases - As Lessee
Remainder of 2019	15,793		15,793
2020	30,909		30,909
2021	25,930		25,930
2022	19,832		19,832
2023	19,089		19,089
2024 and thereafter	26,815		26,815
Total future minimum lease payments	138,368		138,368
Less imputed lease interest	41,138		41,138
Operating lease obligation	97,230		97,230
Rental expense for all operating lease	6,200	$ 3,600	12,100	$ 7,200
Gross profit on sale leaseback transactions	16,100	0	16,100	0
Right of use assets obtained in exchange for new operating lease liabilities	34,500	1,600	34,500	2,200
Prepaid rent and security deposit	$ 7,000	$ 8,300	7,000	8,300
Other information of operating leases
Cash payments			$ 11,677	$ 6,634
Weighted average remaining lease term (in years)	5 years 1 month 17 days	3 years 7 months 10 days	5 years 1 month 17 days	3 years 7 months 10 days
Weighted average discount rate (as a percent)	12.20%	12.00%	12.20%	12.00%
Maximum
Operating Leases
Lease Term - as Lessor	7 years		7 years
Lease Term - as Lessee	9 years		9 years
Minimum
Operating Leases
Lease Term - as Lessor	1 year		1 year
Lease Term - as Lessee	1 year		1 year
Sale Leaseback Agreements
Future minimum lease payments under noncancelable operating leases - As Lessee
Operating lease obligation	$ 59,800	$ 9,200	$ 59,800	$ 9,200
Short term operating lease obligation	9,000	2,600	9,000	2,600
Long term operating lease obligation	$ 50,800	$ 6,600	$ 50,800	$ 6,600