Accumulated Other Comprehensive Income (Loss) - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jul. 01, 2019	Jan. 01, 2019	Jul. 01, 2018	Jan. 01, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	$ 46,509	$ 50,168	$ 42,163	$ 52,826
Other comprehensive income (loss) before reclassifications	(6)	(352)	2,917	(2,574)
Less: amounts reclassified from accumulated other comprehensive income (loss)	(41)	(18)	(151)	(22)
Other comprehensive income (loss)	35	(334)	3,068	(2,552)
Balance at end of period	45,482	46,539	45,482	46,539
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	421	(3,060)	(2,612)	(363)
Balance after cumulative effects					$ 421	$ (2,612)	$ (3,060)	$ (842)
Other comprehensive income (loss)	35	(334)	3,068	(2,552)
Balance at end of period	$ 456	$ (3,394)	$ 456	$ (3,394)
Accounting Standards Update 2016-01
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes								0
Accounting Standards Update 2016-01 | Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes					0	0	0	(556)
Accounting Standards Update 2018-02
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes								0
Accounting Standards Update 2018-02 | Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes					$ 0	$ 0	$ 0	$ 77