Secured Overnight Financing Rate Period

No definition available.

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- Definition

Tenor Spread Adjustment

+ References

No definition available.

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- Definition

Amount of amortization expense attributable to debt issuance costs.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

The average effective interest rate during the reporting period.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Percentage of principal amount of debt redeemed.

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No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Total interest costs incurred during the period and either capitalized or charged against earnings.

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- Definition

Amount of interest expense classified as operating.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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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.

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Amount of assets classified as other.

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- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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Subordinated Debt (Details)		3 Months Ended		12 Months Ended
Subordinated Debt (Details)	Nov. 30, 2025 USD ($)	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 $ / shares	Dec. 31, 2025 USD ($)	Dec. 31, 2005 USD ($)
Line of Credit Facility [Line Items]
Other assets		$ 78,708,000			$ 84,172,000
Tenor spread adjustment		0.0026		0.0026
Interest expense		$ 10,235,000	$ 10,264,000
Depreciation of debt issuance costs		$ 35,000	0
Subordinated debt
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate (percent)		1.37%
Debt instrument, interest rate during period (percent)		5.31%
Junior subordinated debenture, effective interest rate (percent)		3.72%
Junior subordinated debenture		$ 10,000,000.0
Senior Subordinated Notes \| Subordinated Notes Due 2035 (the “Notes”)
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate (percent)	3.48%
Junior subordinated debenture	$ 60,000,000.0
Interest rate, stated percentage	6.875%
Redemption price, percentage	100.00%
Interest costs incurred		1,000,000.0
Debt issuance costs, gross					$ 1,400,000
Depreciation of debt issuance costs		$ 35,000
Percentage of principal amount redeemed	100.00%
Northrim Statutory Trust Two
Line of Credit Facility [Line Items]
Other assets						$ 10,000,000
Junior subordinated notes						$ 10,300,000
Secured overnight financing rate period				90 days
Debt instrument, basis spread on variable rate (percent)				1.37%
Preferred stock, liquidation preference per share (in USD per share) \| $ / shares				$ 1,000
Junior subordinated debenture, effective interest rate (percent)		5.31%			5.35%
Interest expense		$ 138,000	$ 154,000