Leases - Company's weighted average remaining lease term and discount rates used (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Weighted average remaining lease term - Operating leases	11 years 9 months 18 days	10 years 2 months 12 days
Weighted average remaining lease term - Finance leases	12 years 10 months 24 days	3 years 9 months 18 days
Weighted average discount rate - Operating leases (percent)	4.28%	4.74%
Weighted average discount rate - Finance leases (percent)	2.94%	2.97%
Operating cash flows used by operating leases	$ 58,305	$ 61,532
Operating cash flows used by finance leases	1,050	763
Financing cash flows used by finance leases	7,437	7,989
Leased assets obtained in exchange for new operating lease liabilities	90,361	28,762
Leased assets obtained in exchange for new finance lease liabilities	$ 23,117	$ 24,106