Leases (Components of expense and supplemental cash flow information) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Operating
Fixed operating lease expense	$ 25,875
Variable operating lease expense	11,445
Total operating lease expense	37,320
Cash paid for amounts included in the measurement of operating lease liabilities	25,675
ROU assets obtained in exchange for operating lease obligations	0
Finance
Amortization of right of use assets	15,691
Interest expense	1,878
Total finance lease expense	$ 17,569
Weighted average remaining lease term (in years)	1 year 8 months 8 days
Weighted average discount rate	5.20%