Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Leases
Operating lease option to extend	true
Lease expenses:
Operating leases	$ 4,366	$ 3,932
Short-term leases	50	256
Total lease cost	4,416	4,188
Payments for operating leases	5,036	4,440
Right-of-use assets obtained in exchange for lease obligations	$ 3,243	$ 1,534
Remaining lease term (in year)	6 years 2 months 12 days	6 years 10 months 24 days
Discount rate (as a percent)	4.10%	4.30%
Operating lease liabilities
2022	$ 19,690
2023	18,526
2024	17,488
2025	15,765
2026	14,933
Thereafter	24,065
Total lease payments	110,467
Less imputed interest	(14,398)
Total	$ 96,069		$ 94,193
Minimum
Leases
Remaining operating lease term	1 year
Maximum
Leases
Remaining operating lease term	10 years
Operating lease renewal term	5 years