v3.25.2

Fair Value of Financial Instruments - Reconciliation Of Assets Measured at Fair Value On A Recurring Basis (Details) - Municipal Securities - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2025	Dec. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 24,717	$ 20,847
Realized Gains (Losses) Included in Net Income	0	0
Unrealized Gains (Losses) Included in Other Comprehensive Loss	1,803	(2,339)
Purchases	0	9,938
Sales	0	0
Maturities, Prepayments, and Calls	(3,226)	(3,729)
Transfers Into Level 3	0	0
Transfers Out of Level 3	0	0
Ending balance	23,294	24,717
Beginning balance	12,500	7,968
Realized Gains (Losses) Included in Net Income	0	0
Unrealized Gains (Losses) Included in Other Comprehensive Loss	184	782
Purchases	0	5,000
Sales	0	0
Maturities, Prepayments, and Calls	0	(1,250)
Transfers Into Level 3	0	0
Transfers Out of Level 3	0	0
Ending balance	$ 12,684	$ 12,500

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Business First Bancshares, Inc. 10-Q