Parent Only Financial Information Parent Only Income Statement (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Interest and Dividends on Investments	$ 111,896	$ 109,759	$ 96,503
Other Operating Income	3,464	1,477	1,324
Interest Expense	12,694	21,710	12,485
Other Operating Expense	8,964	10,430	9,076
Provision for Income Taxes	11,036	9,600	9,026
Net Income	40,827	37,475	36,279
Parent Company
Condensed Financial Statements, Captions [Line Items]
Dividends from Bank Subsidiaries	17,199	14,100	13,300
Interest and Dividends on Investments	49	49	48
Other Operating Income	246	1,006	907
Total Income	17,494	15,155	14,255
Interest Expense	746	1,024	976
Other Operating Expense	878	875	1,175
Total Expense	1,624	1,899	2,151
Income Before Income Tax Benefit and Equity in Undistributed Net Income of Subsidiaries	15,870	13,256	12,104
Provision for Income Taxes	431	466	686
Equity in Undistributed Net Income of Subsidiaries	24,526	23,753	23,489
Net Income	$ 40,827	$ 37,475	$ 36,279