Regulatory Matters - Summary of Capital Ratios (Detail) $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Company
Total capital (to risk-weighted assets)
Total capital (to risk-weighted assets)	$ 1,226,628	$ 1,167,429
Total capital (to risk-weighted assets), For capital adequacy purposes	912,780	886,420
Tier 1 capital (to risk-weighted assets)
Tier 1 capital (to risk-weighted assets)	1,000,886	948,970
Tier one risk based capital required for capital adequacy with buffer	738,917	717,578
Common equity Tier 1 capital (to risk-weighted assets)
Common equity Tier 1 capital (to risk-weighted assets)	956,233	904,532
Common equity Tier 1 capital (to risk-weighted assets)	608,520	590,946
Tier 1 capital (to average assets)
Tier 1 capital (to average assets)	1,000,886	948,970
Tier 1 capital (to average assets), For capital adequacy purposes	$ 432,091	$ 414,485
Risk Based Ratios [Abstract]
Total capital (to risk-weighted assets), ratio	0.1411	0.1383
Tier 1 capital (to risk-weighted assets), ratio	0.1151	0.1124
Common equity Tier 1 capital (to risk-weighted assets), ratio	0.1100	0.1071
Tier 1 capital (to average assets), ratio	0.0927	0.0916
Total capital (to risk-weighted assets), For capital adequacy purposes , ratio	0.1050	0.1050
Tier one risk based capital required for capital adequacy with buffer to risk weighted assets	8.50%	8.50%
Common equity Tier 1 capital (to risk-weighted assets), For capital adequacy purposes, ratio	7.00%	7.00%
Tier 1 capital (to average assets), For capital adequacy purposes, ratio	0.0400	0.0400
Lakeland
Total capital (to risk-weighted assets)
Total capital (to risk-weighted assets)	$ 1,166,090	$ 1,109,089
Total capital (to risk-weighted assets), For capital adequacy purposes	911,908	885,667
Total capital (to risk - weighted assets), To be well capitalized under prompt corrective action provisions	868,484	843,492
Tier 1 capital (to risk-weighted assets)
Tier 1 capital (to risk-weighted assets)	1,088,605	1,038,661
Tier one risk based capital required for capital adequacy with buffer	738,211	716,968
Tier 1 capital (to risk-weighted assets), To be well capitalized under prompt corrective action provisions	694,787	674,794
Common equity Tier 1 capital (to risk-weighted assets)
Common equity Tier 1 capital (to risk-weighted assets)	1,088,605	1,038,661
Common equity Tier 1 capital (to risk-weighted assets)	607,939	590,444
Common equity Tier 1 capital (to risk-weighted assets), To be well capitalized under prompt corrective action provisions	564,514	548,270
Tier 1 capital (to average assets)
Tier 1 capital (to average assets)	1,088,605	1,038,661
Tier 1 capital (to average assets), For capital adequacy purposes	431,765	414,212
Tier 1 capital (to average assets), To be well capitalized under prompt corrective action provisions	$ 539,707	$ 517,765
Risk Based Ratios [Abstract]
Total capital (to risk-weighted assets), ratio	0.1343	0.1315
Tier 1 capital (to risk-weighted assets), ratio	0.1253	0.1231
Common equity Tier 1 capital (to risk-weighted assets), ratio	0.1253	0.1231
Tier 1 capital (to average assets), ratio	0.1009	0.1003
Total capital (to risk-weighted assets), For capital adequacy purposes , ratio	0.1050	0.1050
Tier one risk based capital required for capital adequacy with buffer to risk weighted assets	8.50%	8.50%
Common equity Tier 1 capital (to risk-weighted assets), For capital adequacy purposes, ratio	7.00%	7.00%
Tier 1 capital (to average assets), For capital adequacy purposes, ratio	0.0400	0.0400
Total capital (to risk - weighted assets), To be well capitalized under prompt corrective action provisions, ratio	0.1000	0.1000
Tier 1 capital (to risk-weighted assets), To be well capitalized under prompt corrective action provisions, ratio	0.0800	0.0800
Common equity Tier 1 capital (to risk-weighted assets), To be well capitalized under prompt corrective action provisions, ratio	6.50%	6.50%
Tier 1 capital (to average assets), To be well capitalized under prompt corrective action provisions, ratio	0.0500	0.0500

Common Equity, Tier One Risk-Based Capital Ratio, Well Capitalized, Minimum

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480696/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480696/942-505-50-1B

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