CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 35,331	$ 23,828	$ 27,381
Other comprehensive income:
Change in net unrealized holding (losses) gains on available-for-sale securities and I/O strips	(6,383)	417	(1,711)
Deferred income taxes	1,925	(175)	719
Change in net unamortized unrealized gain on securities available-for-sale that were reclassified to securities held-to-maturity	(44)	(51)	(116)
Deferred income taxes	13	22	49
Reclassification adjustment for losses (gains) realized in income	(266)	6	(1,099)
Deferred income taxes	79	(3)	461
Change in unrealized (losses) gains on securities and I/O strips, net of deferred income taxes	(4,676)	216	(1,697)
Change in net pension and other benefit plan liability adjustment	2,196	(923)	6
Deferred income taxes	(649)	388	(3)
Change in pension and other benefit plan liability, net of deferred income taxes	1,547	(535)	3
Other comprehensive loss	(3,129)	(319)	(1,694)
Total comprehensive income	$ 32,202	$ 23,509	$ 25,687