Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	108 years
Operating lease cost	$ 2,502
Short-term lease cost	0
Variable lease cost	1,392
Total lease cost	3,894
Cash paid for amonts included in measurement of operating lease liabilities	2,388
Right-of-use assets	89,824	$ 0
Current (included in Accrued liabilities in our Condensed Consolidated Balance Sheet)	3,482
Lease liability	$ 85,759	$ 0
Weighted-average remaining lease term - operating leases (years)	15 years
Weighted-average discount rate - operating leases	5.00%
2019 (remainder)	$ 6,540
2020	7,367
2021	9,448
2022	9,431
2023	9,435
Thereafter	86,075
Total future lease payments	128,296
Less amount representing interest	39,055
Total obligations under operating leases	$ 89,241
Minimum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	1 year
Maximum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	15 years