Parent Company Financial Statements (Statements of Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Dividend income from subsidiary									$ 722	$ 1,315	$ 1,135
Interest on borrowings									3,621	7,456	5,585
Income before income tax expense	$ 19,159	$ 18,184	$ 16,479	$ 17,757	$ 17,479	$ 17,295	$ 15,104	$ 15,899	71,579	65,777	62,354
Income tax benefit (expense)	(3,921)	(3,696)	(3,275)	(3,484)	(3,502)	(3,238)	(2,887)	(3,079)	(14,376)	(12,706)	(33,878)
Net income	$ 15,238	$ 14,488	$ 13,204	$ 14,273	$ 13,977	$ 14,057	$ 12,217	$ 12,820	57,203	53,071	28,476
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Dividend income from subsidiary									36,900	28,100	16,800
Other income									1,128	283	145
Total operating income									38,028	28,383	16,945
Interest on borrowings									3,267	3,415	3,408
Fees to Bank									160	160	160
Other operating expenses									641	569	592
Total operating expenses									4,068	4,144	4,160
Income before equity in undistributed income of subsidiaries and income taxes									33,960	24,239	12,785
Equity in undistributed income of subsidiaries									22,580	27,971	17,405
Income before income tax expense									56,540	52,210	30,190
Income tax benefit (expense)									663	861	(1,714)
Net income									$ 57,203	$ 53,071	$ 28,476