Represents the amount related to discounts on loans receivable.

No definition available.

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

- 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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Namespace Prefix:	rvsb_
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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Namespace Prefix:	rvsb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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

Name:	rvsb_InterestIncomeForegoneOnNonAccrualLoans
Namespace Prefix:	rvsb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Loans Receivable Terms Of Maturity.

+ References

No definition available.

+ Details

Name:	rvsb_LoansReceivableTermsOfMaturity
Namespace Prefix:	rvsb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

maximum loan-to-value ratio.

+ References

No definition available.

+ Details

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

- Definition

Minimum percentage of monthly payments charged off for Consumer installment loan.

+ References

No definition available.

+ Details

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

- Definition

The number of loans to foreign domiciled businesses or foreign countries.

+ References

No definition available.

+ Details

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

- Definition

Represent percentage of loans and extensions of credit outstanding.

+ References

No definition available.

+ Details

Name:	rvsb_PercentageOfLoansAndExtensionsOfCreditOutstanding
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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

+ 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
-SubTopic 20
-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
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix:	us-gaap_
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

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://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-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 ACL - Additional information (Details)	12 Months Ended
LOANS AND ACL - Additional information (Details)	Mar. 31, 2025 USD ($) item	Mar. 31, 2024 USD ($) item	Mar. 31, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Deferred loan fees	$ 4,300,000	$ 4,700,000
Discount On Loans Receivable	1,200,000	1,300,000
Receivable with Imputed Interest, Premium	$ 1,700,000	$ 1,900,000
Number of Loans to Foreign Domiciled Businesses or Foreign Countries \| item	0	0
Percentage Of Loans And Extensions Of Credit Outstanding	15.00%
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss	$ 1,047,086,000	$ 1,008,649,000
Minimum percentage of monthly payments charged off for consumer installment loan	75.00%
Allowance for credit losses (in dollars)	$ 15,374,000	15,364,000	$ 15,309,000
Interest income foregone on non-accrual loans	16,000	10,000	14,000
Non-accrual loans with no ACL	94,000	137,000
Non-accrual loans with ACL	61,000	36,000
Non-accruals, Allowance	1,000	1,000
Total loans	1,062,460,000	1,024,013,000
Assets pledged as collateral \| FHLB and FRB Borrowing Arrangements
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss	756,600,000
Assets pledged as collateral \| Financing receivable \| Commercial Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss	37,000	58,000
Assets pledged as collateral \| Financing receivable \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss	57,000	79,000
Commercial and Industrial \| Commercial Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	232,935,000	229,404,000
Commercial Real Estate Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	950,363,000	925,907,000
Commercial Real Estate Portfolio Segment \| Commercial Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)	5,033,000	5,280,000	3,123,000
Total loans	232,935,000	229,404,000
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)	7,492,000	7,391,000	8,894,000
Total loans	$ 592,185,000	583,501,000
Commercial Real Estate Portfolio Segment \| Raw land loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio	65.00%
Commercial Real Estate Portfolio Segment \| Improved land loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio	75.00%
Commercial Real Estate Portfolio Segment \| Minimum \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio	65.00%
Commercial Real Estate Portfolio Segment \| Maximum \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio	80.00%
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses (in dollars)	$ 1,842,000	1,584,000	$ 1,127,000
Total loans	$ 112,097,000	98,106,000
Consumer \| Real estate one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio	80.00%
Total loans	$ 97,683,000	$ 96,366,000
Consumer \| Minimum \| Real estate one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Terms of maturity	15 years
Consumer \| Maximum \| Real estate one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Terms of maturity	30 years