Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Current tax expense	$ 5,090	$ 7,355	$ 6,125
Deferred tax expense	556	724	882
Deferred tax asset adjustment for tax rate change	0	2,747	0
Total income tax expense	$ 5,646	$ 10,826	$ 7,007