Represents the amount related to discounts on loans receivable.

No definition available.

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- Definition

Amount of deferred interest and fee income, unamortized costs incurred to originate loans unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans covered under loss sharing agreements.

+ References

No definition available.

+ Details

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

- Definition

Amount excluding accrued interest, of allowance for credit loss on non accrual loans.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with allowance for credit loss. Excludes net investment in lease.

+ References

No definition available.

+ Details

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Namespace Prefix:	rvsb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of financing receivables that have been modified.

+ References

No definition available.

+ Details

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Namespace Prefix:	rvsb_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Interest income foregone on loans not accruing. In general, when a loan is 90 days delinquent or when collection of principal or interest appears doubtful, it is placed on non-accrual status, at which time the accrual of interest ceases and a reserve for unrecoverable accrued interest is established and charged against operations. Payments received on non-accrual loans are applied to reduce the outstanding principal balance on a cash-basis method. As a general practice, a loan is not removed from non-accrual status until all delinquent principal, interest and late fees have been brought current and the borrower has demonstrated a history of performance based upon the contractual terms of the note.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of impaired loans of the entity, that were on non-accrual status.

+ References

No definition available.

+ Details

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Namespace Prefix:	rvsb_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The number to one borrower that are over the regulatory limit.

+ References

No definition available.

+ Details

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Namespace Prefix:	rvsb_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

It represent percentage of delinquent loan amount.

+ References

No definition available.

+ Details

Name:	rvsb_PercentageOfDelinquentLoanAmount
Namespace Prefix:	rvsb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represent percentage of loans and extensions of credit outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	rvsb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

+ Details

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

- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

+ Details

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

- Definition

Disclosure of the unamortized amount of the premium on the note or receivable which is added to the face amount of the receivable or loan. The discount or premium is defined as the difference between the present value and the face amount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482925/835-30-45-1A

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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LOANS AND ALLOWANCE FOR CREDIT LOSSES FOR LOANS - Additional information (Details)	3 Months Ended	9 Months Ended		12 Months Ended
	Dec. 31, 2023 USD ($) loan	Dec. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($)	Mar. 31, 2023 USD ($) loan	Sep. 30, 2023 USD ($)	Apr. 01, 2023 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Deferred loan fees	$ 4,700,000	$ 4,700,000		$ 4,400,000
Discount On Loans Receivable	1,300,000	1,300,000		1,400,000
Premiums On Loans Receivable.	1,900,000	1,900,000		$ 2,100,000
Loans Pledged as Collateral	1,002,838,000	$ 1,002,838,000
Percentage Of Loans And Extensions Of Credit Outstanding		15.00%
Number of loans to one borrower over regulatory limit \| loan		0		0
Allowance for credit losses (in dollars)	15,361,000	$ 15,361,000		$ 15,309,000	$ 15,346,000
Non-accrual loans with no ACL	148,000	148,000
Non-accrual loans with ACL	38,000	38,000
Non-accruals, Allowance	1,000	1,000
Interest income foregone on non-accrual loans		8,000	$ 10,000	14,000
Total loans	$ 1,018,199,000	$ 1,018,199,000
Number of loan modifications approved \| loan	0	0
Percentage of delinquent loan amount		75.00%
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts			0
30 To 89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 4,730,000	$ 4,730,000
ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number Of impaired loans on nonaccrual status \| loan						2
Adjustment \| ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)				42,000		$ 42,000
Fully Guaranteed SBA Or USDA Loans \| 30 To 89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,400,000	1,400,000
Asset Pledged as Collateral \| FHLB and FRB Borrowing Arrangements
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Pledged as Collateral	617,900,000	617,900,000
Asset Pledged as Collateral \| Financing receivable \| Commercial Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Pledged as Collateral	63,000	63,000
Asset Pledged as Collateral \| Financing receivable \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Pledged as Collateral	85,000	85,000
Commercial Real Estate Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	920,198,000	920,198,000
Commercial Real Estate Portfolio Segment \| Commercial Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)	5,265,000	5,265,000		3,123,000	5,339,000
Total loans	229,249,000	229,249,000
Commercial Real Estate Portfolio Segment \| Commercial Business \| 30 To 89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	3,896,000	3,896,000
Commercial Real Estate Portfolio Segment \| Commercial Business \| Adjustment \| ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)				1,884,000
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)	7,279,000	7,279,000		8,894,000	7,138,000
Total loans	573,075,000	573,075,000
Commercial Real Estate Portfolio Segment \| Commercial Real Estate \| 30 To 89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	821,000	821,000
Commercial Real Estate Portfolio Segment \| Commercial Real Estate \| Adjustment \| ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)				(1,494,000)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)	1,595,000	1,595,000		1,127,000	$ 1,604,000
Total loans	98,001,000	98,001,000
Consumer \| 30 To 89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	13,000	13,000
Consumer \| Adjustment \| ASU 2016-13
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)				$ 483,000
Consumer \| Real estate one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 96,266,000	$ 96,266,000