Leases - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2017
Operating lease cost
Operating lease expense	$ 4,623
Variable lease expense	3,161
Finance lease cost
Amortization of right-of-use assets	165
Interest on lease liabilities	616
Total lease expense	8,565
Other information
Operating cash flows outflows related to operating leases	6,972
Financing cash flows outflows related to financing leases	379	$ 0
Right-of-use assets obtained in exchange for new finance lease liabilities	$ 17,800
Weighted-average remaining lease term (excluding renewal options) - operating leases	49 years 6 months
Weighted-average remaining lease term (excluding renewal options) -finance leases	65 years 2 months 12 days
Weighted-average discount rate - operating leases	5.70%
Weighted-average discount rate - finance leases	5.40%