Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 13,029	$ 5,090	$ 28,054	$ 5,737
Other comprehensive income:
Change in net actuarial gain	37	26	72	53
Tax effect on change in net actuarial gain	(8)	(5)	(15)	(11)
Unrealized holding gains arising during the period	3,460	2,321	11,233	1,926
Tax effect on unrealized holding gains arising during the period	(727)	(487)	(2,359)	(404)
Reclassification adjustment for gains included in net income	(60)	(381)	(4,201)	(366)
Tax effect on reclassification adjustment for gains included in net income	13	80	883	77
Other comprehensive income, net of tax	2,715	1,554	5,613	1,275
Comprehensive income	$ 15,744	$ 6,644	$ 33,667	$ 7,012