ALLOWANCE FOR LOAN LOSSES (Detail Textuals) - USD ($)	6 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income foregone on non-accrual loans	$ 47,000	$ 52,000
Percentage of delinquent loan amount	75.00%

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.

No definition available.

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