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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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-Section 55
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 20
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Allowance for Credit Losses (Portfolio Credit Quality) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Loan portfolio by credit quality indicator
2023	$ 2,757,552		$ 2,757,552
2022	2,106,857		2,106,857		$ 3,048,975
2021	1,416,323		1,416,323		2,081,483
2020	682,719		682,719		988,625
2019	362,174		362,174		543,277
2018/Prior	571,274		571,274		468,848
Prior					299,395
Total loans	7,896,899		7,896,899		7,430,603
Current-period gross writeoffs
Total	2,569	$ 2,626	7,584	$ 7,047
Commercial, financial and agricultural
Loan portfolio by credit quality indicator
Total loans	4,637,170		4,637,170		4,373,373
Commercial, financial and agricultural \| Domestic \| Commercial.
Loan portfolio by credit quality indicator
2023	640,929		640,929
2022	396,432		396,432		766,789
2021	374,769		374,769		525,241
2020	55,848		55,848		97,498
2019	22,630		22,630		35,917
2018/Prior	66,219		66,219		43,841
Prior					29,468
Total loans	1,556,827		1,556,827		1,498,754
Current-period gross writeoffs
2023			4,747
2022			2,112
2021			10
2020			264
2019			1
Prior			2
Total	2,373	2,568	7,136	6,681
Commercial, financial and agricultural \| Domestic \| Commercial. \| Pass
Loan portfolio by credit quality indicator
2023	639,440		639,440
2022	365,072		365,072		736,462
2021	374,408		374,408		524,879
2020	55,848		55,848		96,401
2019	22,620		22,620		35,917
2018/Prior	66,219		66,219		43,792
Prior					29,464
Total loans	1,523,607		1,523,607		1,466,915
Commercial, financial and agricultural \| Domestic \| Commercial. \| Special Review
Loan portfolio by credit quality indicator
2023	344		344
2022					377
2021	177		177		213
Total loans	521		521		590
Commercial, financial and agricultural \| Domestic \| Commercial. \| Watch List - Substandard
Loan portfolio by credit quality indicator
2023	1,145		1,145
2022	180		180		161
2021	95		95		149
2020					143
2019	10		10
2018/Prior					49
Total loans	1,430		1,430		502
Commercial, financial and agricultural \| Domestic \| Commercial. \| Watch List - Doubtful
Loan portfolio by credit quality indicator
2022	31,180		31,180		29,789
2021	89		89
2020					954
Prior					4
Total loans	31,269		31,269		30,747
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial
Loan portfolio by credit quality indicator
2023	846,206		846,206
2022	668,892		668,892		833,401
2021	444,678		444,678		584,381
2020	314,095		314,095		511,194
2019	187,879		187,879		232,633
2018/Prior	284,923		284,923		325,214
Prior					81,295
Total loans	2,746,673		2,746,673		2,568,118
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial \| Pass
Loan portfolio by credit quality indicator
2023	703,208		703,208
2022	666,498		666,498		811,117
2021	435,773		435,773		584,134
2020	311,648		311,648		456,200
2019	187,792		187,792		232,537
2018/Prior	284,923		284,923		325,214
Prior					81,295
Total loans	2,589,842		2,589,842		2,490,497
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial \| Special Review
Loan portfolio by credit quality indicator
2023	694		694
2022					2,855
2021	8,670		8,670
2020					842
Total loans	9,364		9,364		3,697
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial \| Watch List - Pass
Loan portfolio by credit quality indicator
2023	21,297		21,297
2022	87		87		17,060
2021	235		235		247
Total loans	21,619		21,619		17,307
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial \| Watch List - Substandard
Loan portfolio by credit quality indicator
2023	120,796		120,796
2022	2,220		2,220		2,275
2020	2,447		2,447		54,152
2019	87		87		96
Total loans	125,550		125,550		56,523
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial \| Watch List - Doubtful
Loan portfolio by credit quality indicator
2023	211		211
2022	87		87		94
Total loans	298		298		94
Commercial, financial and agricultural \| Domestic \| Commercial real estate: multifamily
Loan portfolio by credit quality indicator
2023	115,982		115,982
2022	94,466		94,466		127,797
2021	42,244		42,244		87,469
2020	32,487		32,487		59,035
2019	11,223		11,223		12,026
2018/Prior	37,268		37,268		5,490
Prior					14,684
Total loans	333,670		333,670		306,501
Commercial, financial and agricultural \| Domestic \| Commercial real estate: multifamily \| Pass
Loan portfolio by credit quality indicator
2023	115,982		115,982
2022	94,366		94,366		127,680
2021	42,244		42,244		87,469
2020	32,487		32,487		59,035
2019	11,223		11,223		12,026
2018/Prior	37,268		37,268		5,490
Prior					14,684
Total loans	333,570		333,570		306,384
Commercial, financial and agricultural \| Domestic \| Commercial real estate: multifamily \| Watch List - Doubtful
Loan portfolio by credit quality indicator
2022	100		100		117
Total loans	100		100		117
Obligations of states and political subdivisions
Loan portfolio by credit quality indicator
Total loans	2,126,302		2,126,302		1,989,669
Obligations of states and political subdivisions \| Domestic \| Commercial Real Estate: other construction and land development
Loan portfolio by credit quality indicator
2023	806,430		806,430
2022	716,500		716,500		933,657
2021	369,830		369,830		666,754
2020	158,043		158,043		173,918
2019	71,973		71,973		175,106
2018/Prior	3,526		3,526		35,069
Prior					5,165
Total loans	2,126,302		2,126,302		1,989,669
Current-period gross writeoffs
Total				2
Obligations of states and political subdivisions \| Domestic \| Commercial Real Estate: other construction and land development \| Pass
Loan portfolio by credit quality indicator
2023	787,509		787,509
2022	703,627		703,627		913,675
2021	360,600		360,600		666,347
2020	158,043		158,043		173,824
2019	71,766		71,766		174,897
2018/Prior	3,526		3,526		35,069
Prior					5,165
Total loans	2,085,071		2,085,071		1,968,977
Obligations of states and political subdivisions \| Domestic \| Commercial Real Estate: other construction and land development \| Special Review
Loan portfolio by credit quality indicator
2021	9,230		9,230
2019	207		207		209
Total loans	9,437		9,437		209
Obligations of states and political subdivisions \| Domestic \| Commercial Real Estate: other construction and land development \| Watch List - Substandard
Loan portfolio by credit quality indicator
2023	18,835		18,835
2022	2,872		2,872
Total loans	21,707		21,707
Obligations of states and political subdivisions \| Domestic \| Commercial Real Estate: other construction and land development \| Watch List - Doubtful
Loan portfolio by credit quality indicator
2023	86		86
2022	10,001		10,001		19,982
2021					407
2020					94
Total loans	10,087		10,087		20,483
Real estate - mortgage
Loan portfolio by credit quality indicator
Total loans	907,615		907,615		865,994
Real estate - mortgage \| Domestic \| Residential: first lien
Loan portfolio by credit quality indicator
2023	147,037		147,037
2022	86,237		86,237		138,848
2021	70,420		70,420		82,826
2020	41,074		41,074		49,591
2019	29,566		29,566		40,985
2018/Prior	82,063		82,063		33,814
Prior					79,660
Total loans	456,397		456,397		425,724
Current-period gross writeoffs
Prior			43
Total	43	3	43	159
Real estate - mortgage \| Domestic \| Residential: first lien \| Pass
Loan portfolio by credit quality indicator
2023	147,037		147,037
2022	86,132		86,132		138,771
2021	70,085		70,085		82,466
2020	41,074		41,074		49,591
2019	29,566		29,566		40,985
2018/Prior	82,063		82,063		33,814
Prior					79,660
Total loans	455,957		455,957		425,287
Real estate - mortgage \| Domestic \| Residential: first lien \| Watch List - Substandard
Loan portfolio by credit quality indicator
2021	335		335		360
Total loans	335		335		360
Real estate - mortgage \| Domestic \| Residential: first lien \| Watch List - Doubtful
Loan portfolio by credit quality indicator
2022	105		105		77
Total loans	105		105		77
Real estate - mortgage \| Domestic \| Residential Junior Lien
Loan portfolio by credit quality indicator
2023	64,305		64,305
2022	80,318		80,318		92,256
2021	99,826		99,826		109,127
2020	78,783		78,783		91,130
2019	35,860		35,860		41,273
2018/Prior	92,126		92,126		21,975
Prior					84,509
Total loans	451,218		451,218		440,270
Current-period gross writeoffs
Prior			283
Total	118		283	28
Real estate - mortgage \| Domestic \| Residential Junior Lien \| Pass
Loan portfolio by credit quality indicator
2023	63,987		63,987
2022	80,318		80,318		92,256
2021	99,826		99,826		108,815
2020	78,783		78,783		91,130
2019	35,860		35,860		41,273
2018/Prior	92,126		92,126		21,975
Prior					84,509
Total loans	450,900		450,900		439,958
Real estate - mortgage \| Domestic \| Residential Junior Lien \| Watch List - Doubtful
Loan portfolio by credit quality indicator
2023	318		318
2021					312
Total loans	318		318		312
Consumer
Loan portfolio by credit quality indicator
Total loans	44,767		44,767		41,592
Consumer \| Domestic
Loan portfolio by credit quality indicator
2023	31,491		31,491
2022	9,939		9,939		31,962
2021	1,471		1,471		6,603
2020	280		280		897
2019	183		183		489
2018/Prior	1,403		1,403		28
Prior					1,613
Total loans	44,767		44,767		41,592
Current-period gross writeoffs
2023			22
2022			92
2021			7
Prior			1
Total	35	$ 55	122	$ 177
Consumer \| Domestic \| Pass
Loan portfolio by credit quality indicator
2023	31,491		31,491
2022	9,939		9,939		31,962
2021	1,471		1,471		6,603
2020	280		280		897
2019	183		183		489
2018/Prior	1,403		1,403		28
Prior					1,613
Total loans	44,767		44,767		41,592
Foreign.
Loan portfolio by credit quality indicator
Total loans	181,045		181,045		159,975
Foreign. \| Foreign
Loan portfolio by credit quality indicator
2023	105,172		105,172
2022	54,073		54,073		124,265
2021	13,085		13,085		19,082
2020	2,109		2,109		5,362
2019	2,860		2,860		4,848
2018/Prior	3,746		3,746		3,417
Prior					3,001
Total loans	181,045		181,045		159,975
Foreign. \| Foreign \| Pass
Loan portfolio by credit quality indicator
2023	105,172		105,172
2022	54,073		54,073		124,265
2021	13,085		13,085		19,082
2020	2,109		2,109		5,362
2019	2,860		2,860		4,848
2018/Prior	3,746		3,746		3,417
Prior					3,001
Total loans	$ 181,045		$ 181,045		$ 159,975