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- Definition

Tenor Spread Adjustment

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No definition available.

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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.

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No definition available.

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

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

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

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

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Percentage of principal amount of debt redeemed.

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No definition available.

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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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Amount of interest expense classified as operating.

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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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Amount of assets classified as other.

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Subordinated Debt (Details)		3 Months Ended		6 Months Ended	9 Months Ended
Subordinated Debt (Details)	Nov. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Jun. 30, 2025	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 $ / shares	Dec. 31, 2005 USD ($)
Line of Credit Facility [Line Items]
Other assets		$ 103,761,000			$ 103,761,000		$ 84,172,000
Tenor spread adjustment		0.0026			0.0026			0.0026
Interest expense		$ 10,276,000	$ 10,632,000		$ 30,529,000	$ 32,103,000
Depreciation of debt issuance costs					$ 104,000	0
Subordinated debt
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate (percent)					1.37%
Junior subordinated debenture, effective interest rate (percent)		3.72%			3.72%
Junior subordinated debenture		$ 10,000,000.0			$ 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			3,100,000
Debt issuance costs, gross							$ 1,400,000
Depreciation of debt issuance costs		$ 35,000			$ 105,000
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)		5.53%			5.53%		5.35%
Interest expense		$ 141,000	$ 155,000		$ 417,000	$ 464,000