Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Consolidated Statements of Comprehensive Income (Unaudited) [Abstract]
Net income	$ 14,433	$ 11,254	$ 28,516	$ 24,567
Net unrealized holding gain (loss) on securities available for sale	844	927	(5,174)	11,659
Reclassification adjustments for net gain recognized in income	0	0	0	(1,155)
Tax effect	(222)	(242)	1,335	(2,729)
Net unrealized gain (loss) on securities available for sale, net of tax	622	685	(3,839)	7,775
Amortization of net actuarial gain	(169)	(143)	(397)	(309)
Amortization of prior service cost (credit)	102	(49)	50	(98)
Tax effect	17	51	90	107
Amortization of net actuarial gain and prior service cost (credit) on pension and postretirement plans, net of tax	(50)	(141)	(257)	(300)
Other comprehensive income (loss), net of tax	572	544	(4,096)	7,475
Comprehensive income	$ 15,005	$ 11,798	$ 24,420	$ 32,042