v3.25.2

Investments - Amortized Cost and Estimated Fair Value - Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Debt Securities, Held-to-Maturity, Fair Value to Amortized Cost, after Allowance for Credit Loss [Abstract]
Amortized Cost	$ 298,499	$ 305,529
Gross Unrecognized Gains	75	229
Gross Unrecognized Losses	(16,872)	(14,730)
Allowance for credit losses on held-to-maturity securities	(15)	(15)
Securities held-to-maturity	281,702	291,028
U.S. government agencies
Debt Securities, Held-to-Maturity, Fair Value to Amortized Cost, after Allowance for Credit Loss [Abstract]
Amortized Cost	4,678	4,819
Gross Unrecognized Losses	(426)	(592)
Securities held-to-maturity	4,252	4,227
Mortgage-backed securities
Debt Securities, Held-to-Maturity, Fair Value to Amortized Cost, after Allowance for Credit Loss [Abstract]
Amortized Cost	122,149	128,974
Gross Unrecognized Gains	2
Gross Unrecognized Losses	(9,454)	(13,986)
Securities held-to-maturity	112,697	114,988
State and political subdivisions
Debt Securities, Held-to-Maturity, Fair Value to Amortized Cost, after Allowance for Credit Loss [Abstract]
Amortized Cost	171,672	171,736
Gross Unrecognized Gains	73	229
Gross Unrecognized Losses	(6,992)	(152)
Allowance for credit losses on held-to-maturity securities	(15)	(15)
Securities held-to-maturity	$ 164,753	$ 171,813

Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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SIERRA BANCORP 10-Q