Segment Information (Segment Financial Information) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Net Interest Income	$ 41,287			$ 38,388			$ 120,099	$ 113,103
Net Gains on Sales of Loans	2,197			2,861			6,417	7,378
Net Gains on Securities	218			607			1,493	2,190
Trust and Investment Product Fees	2,690			1,957			7,668	5,855
Insurance Revenues	2,007			1,989			7,319	7,048
Noncash Items:
Provision (Benefit) for Credit Losses	(2,000)			4,500			(8,500)	15,550
Depreciation and Amortization	2,142			2,335			6,723	7,043
Income Tax Expense (Benefit)	4,913			3,154			15,489	8,180
Segment Profit (Loss)	21,486	$ 23,822	$ 19,557	14,593	$ 14,255	$ 12,472	64,865	41,320
Segment Assets	5,475,750						5,475,750		$ 4,977,577
Operating Segments | Core Banking
Segment Reporting Information [Line Items]
Net Interest Income	41,925			39,039			122,028	115,148
Net Gains on Sales of Loans	2,197			2,861			6,417	7,378
Net Gains on Securities	218			607			1,493	2,190
Trust and Investment Product Fees	1			2			4	3
Insurance Revenues	2			6			9	11
Noncash Items:
Provision (Benefit) for Credit Losses	(2,000)			4,500			(8,500)	15,550
Depreciation and Amortization	2,038			2,237			6,403	6,748
Income Tax Expense (Benefit)	5,069			3,268			15,549	8,635
Segment Profit (Loss)	21,267			14,628			63,204	40,573
Segment Assets	5,465,132						5,465,132		4,963,655
Operating Segments | Wealth Management Services
Segment Reporting Information [Line Items]
Net Interest Income	15			4			36	12
Net Gains on Sales of Loans	0			0			0	0
Net Gains on Securities	0			0			0	0
Trust and Investment Product Fees	2,689			1,955			7,664	5,852
Insurance Revenues	3			1			6	12
Noncash Items:
Provision (Benefit) for Credit Losses	0			0			0	0
Depreciation and Amortization	11			2			35	4
Income Tax Expense (Benefit)	233			108			583	336
Segment Profit (Loss)	722			321			1,811	991
Segment Assets	5,819						5,819		4,480
Operating Segments | Insurance
Segment Reporting Information [Line Items]
Net Interest Income	3			2			8	9
Net Gains on Sales of Loans	0			0			0	0
Net Gains on Securities	0			0			0	0
Trust and Investment Product Fees	0			0			0	0
Insurance Revenues	2,002			1,982			7,304	7,025
Noncash Items:
Provision (Benefit) for Credit Losses	0			0			0	0
Depreciation and Amortization	13			16			44	50
Income Tax Expense (Benefit)	79			71			575	471
Segment Profit (Loss)	250			216			1,812	1,437
Segment Assets	12,350						12,350		10,263
Other
Segment Reporting Information [Line Items]
Net Interest Income	(656)			(657)			(1,973)	(2,066)
Net Gains on Sales of Loans	0			0			0	0
Net Gains on Securities	0			0			0	0
Trust and Investment Product Fees	0			0			0	0
Insurance Revenues	0			0			0	0
Noncash Items:
Provision (Benefit) for Credit Losses	0			0			0	0
Depreciation and Amortization	80			80			241	241
Income Tax Expense (Benefit)	(468)			(293)			(1,218)	(1,262)
Segment Profit (Loss)	(753)			$ (572)			(1,962)	$ (1,681)
Segment Assets	$ (7,551)						$ (7,551)		$ (821)