Income Taxes (Reconciliation of Expected Income Tax Benefit Computed Using Federal Statutory Income Tax Rate) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Computed tax expense									$ 15,623	$ 15,032	$ 13,813
State taxes, net of federal benefit									1,132	1,003	905
Tax exempt income									(894)	(738)	(741)
Income from life insurance									(532)	(509)	(510)
Low income housing credits									(500)	(430)	(465)
Share-based awards									33	(60)	(250)
Other									48	78	(46)
Income tax expense	$ 4,564	$ 4,194	$ 2,752	$ 3,400	$ 3,921	$ 3,696	$ 3,275	$ 3,484	14,910	14,376	12,706
Income before income taxes	$ 22,842	$ 20,969	$ 13,692	$ 16,893	$ 19,159	$ 18,184	$ 16,479	$ 17,757	$ 74,396	$ 71,579	$ 65,777
Effective tax rate									20.00%	20.10%	19.30%