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Basis of Accounting and Consolidation - Additional Information (Details) - USD ($)				3 Months Ended		9 Months Ended		12 Months Ended
	Feb. 14, 2022	Sep. 10, 2021	Feb. 22, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Summary Of Significant Accounting Policies [Line Items]
Common stock, par value (in dollars per share)				$ 4		$ 4		$ 4
Loans acquired		$ 208,000,000
Deposits		215,000,000		$ 5,483,198,000		$ 5,483,198,000		$ 4,956,486,000
Core deposit intangible asset		$ 4,900,000
Amortization period		10 years
Stock plans, term						10 years
Maximum number of shares to be issued in stock incentive plan (in shares)				399,983		399,983
Employee discount for employee stock purchase plan						15.00%
Employee stock purchase plan, number of shares authorized				600,000		600,000
Stock issued during period, shares, employee stock purchase plans				6,104	2,700	14,430	8,439
Captive maximum gross premiums						$ 2,450,000
Stock Options
Summary Of Significant Accounting Policies [Line Items]
Common stock awarded in SI plan (in shares)						0
Restricted Stock
Summary Of Significant Accounting Policies [Line Items]
Common stock awarded in SI plan (in shares)						61,400		30,125
Restricted Stock Units (RSUs)
Summary Of Significant Accounting Policies [Line Items]
Common stock awarded in SI plan (in shares)						37,150		35,400
Delta Bancshares Company
Summary Of Significant Accounting Policies [Line Items]
Percentage of issued and outstanding shares acquired	100.00%
Common stock, par value (in dollars per share)	$ 10.00
Share Price	$ 4.00
Consideration payable in cash	$ 15,150,000
Consideration payable in shares	2,292,270
LINCO Bancshares, Inc.
Summary Of Significant Accounting Policies [Line Items]
Percentage of issued and outstanding shares acquired			100.00%
Common stock, par value (in dollars per share)			$ 1.00
Share Price			$ 4.00
Consideration payable in cash			$ 103,500,000
Consideration payable in shares			1,262,246
Dividends			$ 13,000,000

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