Trust Preferred Securities - Summary of Debentures Payable to Statutory Trusts (Details) (Parenthetical) - Subordinated Debt	3 Months Ended
Mar. 31, 2026
First Bancshares of Baton Rouge Statutory Trust I
Debt Instrument [Line Items]
Basis spread on variable rate	2.50%
Basis spread adjustment	0.26161%
State Capital Statutory Trust IV
Debt Instrument [Line Items]
Basis spread on variable rate	1.99%
Basis spread adjustment	0.26161%
BancPlus Statutory Trust II
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%
Basis spread adjustment	0.26161%
BancPlus Statutory Trust III
Debt Instrument [Line Items]
Basis spread on variable rate	1.35%
Basis spread adjustment	0.26161%
State Capital Master Trust
Debt Instrument [Line Items]
Basis spread on variable rate	1.46%
Basis spread adjustment	0.26161%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details