Operating Leases - Cost and Supplemental Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Leases [Abstract]
Operating lease cost	$ 576	$ 649	$ 1,267	$ 1,273
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	694	669	1,427	1,319
Right of use assets obtained in exchange for lease obligations	17	$ 1,523	54	$ 1,588
Operating leases:
Operating lease assets	7,843		7,843		$ 8,991
Operating lease liabilities	$ 8,758		$ 8,758		$ 9,990
Weighted-average remaining lease term	4 years 7 months 6 days		4 years 7 months 6 days		5 years
Weighted-average discount rate	2.72%		2.72%		2.81%