Adoption of New Accounting Pronouncements and Issued Not Yet Effective Accounting Standards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase	$ 52
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	83,197	$ 85,379	$ 85,675	$ 56,679
Off-Balance Sheet, Credit Loss, Liability	4,282	5,214	116
Net deferred tax asset (liability)	450		2,892
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	1,110,759	1,069,226	1,040,256
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	6,871,122	7,141,891	7,177,785
Commercial Financial Agricultural [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			25,608
Commercial Real Estate Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			23,480
Construction Real Estate [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			7,288
Residential real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			11,363
Consumer Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			17,418
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	3,002,936
Finance Leases Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			518
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase	52
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	6,090		6,090
Off-Balance Sheet, Credit Loss, Liability	3,900		3,866
Net deferred tax asset (liability)	(2,100)		(2,115)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(8,000)		(7,956)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss			(119)
Cumulative Effect, Period of Adoption, Adjustment | Commercial Financial Agricultural [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			(8,257)
Cumulative Effect, Period of Adoption, Adjustment | Commercial Real Estate Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			2,119
Cumulative Effect, Period of Adoption, Adjustment | Construction Real Estate [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			(1,898)
Cumulative Effect, Period of Adoption, Adjustment | Residential real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			3,121
Cumulative Effect, Period of Adoption, Adjustment | Consumer Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			10,925
Cumulative Effect, Period of Adoption, Adjustment | Finance Leases Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			80
Cumulative Effect, Period of Adoption, Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			91,765
Off-Balance Sheet, Credit Loss, Liability			3,982
Net deferred tax asset (liability)			777
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			1,032,300
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss			7,177,666
Cumulative Effect, Period of Adoption, Adjusted Balance | Commercial Financial Agricultural [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			17,351
Cumulative Effect, Period of Adoption, Adjusted Balance | Commercial Real Estate Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			25,599
Cumulative Effect, Period of Adoption, Adjusted Balance | Construction Real Estate [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			5,390
Cumulative Effect, Period of Adoption, Adjusted Balance | Residential real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			14,484
Cumulative Effect, Period of Adoption, Adjusted Balance | Consumer Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			28,343
Cumulative Effect, Period of Adoption, Adjusted Balance | Finance Leases Portfolio Segment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			598
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	776,294	$ 847,235	704,764	$ 646,847
Accounting Standards Update 2016-13 | Retained Earnings | Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity Attributable to Noncontrolling Interest	$ 8,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			(7,956)
Accounting Standards Update 2016-13 | Retained Earnings | Cumulative Effect, Period of Adoption, Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			$ 696,808