v3.25.3

Allowance for Credit Losses on Loans - Narrative (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Financing Receivable, Allowance for Credit Losses [Line Items]
Nonaccrual loans	$ 114,265,000	$ 108,529,000
90 days past due, still accruing	0	11,500,000
Average recorded investment nonaccrual status	121,300,000	$ 63,400,000
Unfunded commitments modified during period	0
Loans that were modified with in the previous 12 months	1,000,000
Extended Maturity
Financing Receivable, Allowance for Credit Losses [Line Items]
Amount of financing receivable modified in period	$ 17,600,000

Average recorded investment in financing receivables after undergoing trouble debt restructuring that are on nonaccrual status as of the balance sheet date.

+ References

No definition available.

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- Definition

Off-Balance-Sheet, Credit Loss, Liability, Modified In Period, Amount

+ References

No definition available.

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- Definition

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.

+ References

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- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

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- Definition

Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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- Definition

Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

+ References

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First Guaranty Bancshares, Inc. 10-Q