Leases - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Lessee, Lease, Description [Line Items]
Operating lease liabilities		$ 10,599
Current portion of operating lease liabilities		2,099
Operating lease right of use assets		9,636
Decrease of accrued liabilities		$ (15,164)	$ (13,723)
Renewal term		10 years
Operating lease payments		$ 3,678
Rental payment of leases			$ 3,217	$ 2,847
Weighted-average remaining lease term		5 years
Discount rate		4.42%
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term		1 month
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term		8 years
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Operating lease liabilities	$ 10,684
Current portion of operating lease liabilities	2,362
Operating lease right of use assets	8,842
Decrease of accrued liabilities	819
Decrease in retained earnings	39
Accounting Standards Update 2016-02 | Build to suit lease
Lessee, Lease, Description [Line Items]
Decrease of accrued liabilities	$ 3,346