v3.25.3

AFS Securities - Amortized Cost and Fair Value of AFS Securities, with Gross Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Total	$ 524,534	$ 515,516
Gross Unrealized Gains	1,107	9
Gross Unrealized Losses	13,671	26,496
Fair Value	511,970	489,029
U.S. Treasury
Debt Securities, Available-for-sale [Line Items]
Total	210,462	230,807
Gross Unrealized Gains	0	0
Gross Unrealized Losses	4,421	10,236
Fair Value	206,041	220,571
States and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Total	74,042	81,135
Gross Unrealized Gains	26	9
Gross Unrealized Losses	2,966	4,576
Fair Value	71,102	76,568
Auction Rate Money Market Preferred
Debt Securities, Available-for-sale [Line Items]
Total	3,200	3,200
Gross Unrealized Gains	0	0
Gross Unrealized Losses	410	156
Fair Value	2,790	3,044
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Total	24,696	29,068
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,299	2,182
Fair Value	23,397	26,886
Collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Total	203,984	163,156
Gross Unrealized Gains	1,081	0
Gross Unrealized Losses	3,852	8,482
Fair Value	201,213	154,674
Corporate
Debt Securities, Available-for-sale [Line Items]
Total	8,150	8,150
Gross Unrealized Gains	0	0
Gross Unrealized Losses	723	864
Fair Value	$ 7,427	$ 7,286

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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ISABELLA BANK CORP 10-Q