Leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Leases
Operating lease option to extend			true
Lease expenses:
Operating leases	$ 4,144	$ 3,356	$ 12,110	$ 9,817
Short-term leases	457	213	937	644
Sublease income		(35)		(94)
Total lease cost	4,601	3,534	13,047	10,367
Cash payments for operating leases	4,418	4,063	13,212	11,793
Upon adoption of ASU 2016-02				58,713
New leases	1,721	1,929	8,219	1,929
Right-of-use assets obtained in exchange for lease obligations	$ 1,721	$ 1,929	$ 8,219	$ 60,642
Remaining lease term (in year)	6 years 4 months 24 days	5 years 9 months 18 days	6 years 4 months 24 days	5 years 9 months 18 days
Discount rate (as a percent)	4.20%	4.60%	4.20%	4.60%
Operating lease liabilities
2021	$ 18,586		$ 18,586
2022	16,405		16,405
2023	16,792		16,792
2024	14,474		14,474
2025	13,296		13,296
Thereafter	27,224		27,224
Total lease payments	106,777		106,777
Less imputed interest	(14,772)		(14,772)
Total	$ 92,005		$ 92,005		$ 91,320
Minimum
Leases
Remaining operating lease term			1 year
Maximum
Leases
Remaining operating lease term			10 years
Operating lease renewal term	5 years		5 years