Represents an extended maturity period of loans receivable.

No definition available.

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

- Definition

It represent percentage of delinquent loan amount.

+ References

No definition available.

+ Details

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Data Type:	num: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, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

+ Details

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

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

+ Details

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

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

+ Details

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

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialLoanMember
Namespace Prefix:
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Balance Type:
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- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialRealEstateMember
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- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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- Details

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Namespace Prefix:
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- Details

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ALLOWANCE FOR LOAN LOSSES - Additional information (Details)	6 Months Ended
	Sep. 30, 2019 USD ($) item	Sep. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income foregone on non-accrual loans	$ 36,681	$ 47,000
Percentage of delinquent loan amount	75.00%
Loans and leases receivable, allowance	$ 11,436,000	11,513,000	$ 11,442,000	$ 11,457,000	$ 11,349,000	$ 10,766,000
Commercial Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans default \| item	1
Loans and leases receivable, allowance	$ 150,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans default \| item	2
Loans and leases receivable, allowance	$ 1,000,000
Commercial Real Estate Portfolio Segment \| Commercial and Constructions
Accounts, Notes, Loans and Financing Receivable [Line Items]
Post-modification outstanding recorded investment amount	27,000	26,000
Commercial Real Estate Portfolio Segment \| Commercial Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, allowance	2,051,000	1,858,000	2,113,000	1,808,000	1,799,000	1,668,000
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, allowance	5,038,000	5,361,000	4,889,000	5,053,000	5,139,000	4,914,000
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases receivable, allowance	$ 1,347,000	$ 1,641,000	$ 1,346,000	$ 1,447,000	$ 1,788,000	$ 1,809,000
Consumer \| Real estate one-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extended maturity period of loans receivable	10 years