Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Comprehensive Income Net Of Tax [Abstract]
Unrealized holding gains (losses) on available-for-sale securities during the year, pre-tax		$ 15,836	$ 17,513	$ (5,343)
Reclassification adjustment for (gains) losses included in net income, pre-tax	[1]	430	11	(283)
Net other comprehensive income (loss), pre-tax		16,266	17,524	(5,626)
Unrealized holding gains (losses) on available-for-sale securities during the year, tax		(3,970)	(3,666)	1,110
Reclassification adjustment for (gains) losses included in net income, tax	[1]	(90)	(2)	59
Net other comprehensive income (loss), tax		(4,060)	(3,668)	1,169
Unrealized holding gains (losses) on available-for-sale securities during the year, after tax		11,866	13,847	(4,233)
Reclassification adjustment for (gains) losses included in net income, after-tax	[1]	340	9	(224)
Net other comprehensive income (loss), after-tax		$ 12,206	$ 13,856	$ (4,457)

[1] Pre-tax reclassification adjustments relating to available-for-sale securities are reported in security gains and the tax impact is included in income tax expense on the consolidated statements of income.