The amount of plan compensation cost recognized during the period, net of dividends received.

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
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-Topic 718
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-Section 50
-Paragraph 2
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-Publisher FASB
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Topic 718
-SubTopic 10
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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-Topic 718
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (c)(2)(i)
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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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-Topic 718
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-Section 50
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Note 10 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended		9 Months Ended
	Jan. 01, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023	Dec. 31, 2022	May 31, 2020
Employee Stock Ownership Plan (ESOP), Compensation Expense, Net of Dividends Received		$ 167,000	$ 216,000	$ 507,000	$ 752,000
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)		120,410		120,410		132,918	166,839
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		3,100		32,449	55,443
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 1,200,000		$ 1,200,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				1 year 4 months 2 days
Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				1 year
Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				5 years
First Northwest Bancorp 2020 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)								520,000
Employee Stock Ownership Plan (ESOP), Compensation Expense, Net of Dividends Received				$ 85,490
First Northwest Bancorp 2015 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)		0		0
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)		34,920		34,920
The Equity Incentive Plans [Member]
Share-Based Payment Arrangement, Expense		$ 349,000	404,000	$ 1,100,000	$ 1,300,000
The Equity Incentive Plans [Member] \| Director [Member]
Share-Based Payment Arrangement, Expense	$ 190,000	$ 59,000	$ 50,000		$ 189,000