Nominal or face amount used to calculate payment on derivative.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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+ Details

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

- 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 of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
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+ Details

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

- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
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Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=rmni_AccumulatedOtherComprehensiveIncomeLossMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

FINANCIAL INSTRUMENTS AND SIGNIFICANT CONCENTRATIONS - Amounts Recorded For Interest Rate Swap Agreement (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	May 18, 2022	Dec. 31, 2021
Deposits and other
Derivatives, Fair Value [Line Items]
Interest rate swap	$ 1,550		$ 1,550			$ 0
Accumulated other comprehensive loss
Derivatives, Fair Value [Line Items]
Interest rate swap	1,220		1,220			$ 0
Interest rate swap agreement
Derivatives, Fair Value [Line Items]
Notional amount					$ 40,000
Interest rate swap	1,500		1,500
Interest expense	$ 81	$ 0	$ 224	$ 0