The ability to access Federal Reserve Bank's Discount Window on a collateralized basis.

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Increase

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Secured Debt, Additional Amount Pledged

+ References

No definition available.

+ Details

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Namespace Prefix:	finw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
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-Name Accounting Standards Codification
-Section S99
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482454/460-10-45-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=finw_PaycheckProtectionProgramLiquidityFacilityMember
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- Details

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- Details

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- Details

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- Details

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- Details

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Commitments and Contingent Liabilities - Narrative (Details) - USD ($)	1 Months Ended	6 Months Ended
	Aug. 14, 2023	Jun. 30, 2023	Jun. 30, 2022	Mar. 31, 2023	Dec. 31, 2022	Apr. 20, 2020
Line of Credit Facility [Line Items]
PPP Liquidity Facility		$ 252,000			$ 314,000
Allowance for credit losses on unfunded commitments		41,500		$ 29,000	0
Paycheck Protection Program Liquidity Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity		300,000			300,000
Fixed rate						0.35%
Average outstanding borrowings		300,000	$ 800,000
Line of Credit
Line of Credit Facility [Line Items]
PPP Liquidity Facility		0			0
Federal Reserve Bank borrowings on collateral		10,400,000			10,600,000
Term Funding Program
Line of Credit Facility [Line Items]
Federal Reserve Bank borrowings on collateral		800,000
Zion Bank \| Line of Credit
Line of Credit Facility [Line Items]
Unsecured line available					1,000,000
Zion Bank \| Line of Credit \| Subsequent Event
Line of Credit Facility [Line Items]
Unsecured line available	$ 5,000,000
Bank of the West \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity		1,050,000.00			1,050,000.00
Federal Home Loan Bank Secured Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity		2,500,000			2,600,000
PPP Liquidity Facility		0			0
Loans		$ 3,800,000			$ 4,000,000
Federal Home Loan Bank Secured Line of Credit \| Subsequent Event
Line of Credit Facility [Line Items]
Additional loans pledged	46,900,000
Increase in maximum borrowing capacity	$ 30,900,000