Represents the leverage ratio of credit facility.

No definition available.

Name:	rei_LeverageRatioTotal
Namespace Prefix:	rei_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
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

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_FederalFundsPurchasedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

REVOLVING LINE OF CREDIT (Details) - USD ($)			3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
REVOLVING LINE OF CREDIT (Details) - USD ($)	Apr. 09, 2019	Feb. 25, 2019	Mar. 31, 2019	Jun. 30, 2019	Sep. 30, 2019	Dec. 31, 2019	Apr. 30, 2019	Dec. 31, 2018	Jun. 01, 2018	Jul. 01, 2014
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity							$ 1,000,000,000
Debt Instrument, Basis Spread on Variable Rate				0.00%	0.00%	0.00%
Long-term Line of Credit			$ 84,500,000	$ 360,500,000	$ 366,500,000	$ 366,500,000		$ 39,500,000
Line of Credit Facility, Expiration Period		5 years
Line of Credit Facility, Current Borrowing Capacity							$ 425,000,000
Minimum
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity									$ 60,000,000
Debt Instrument, Basis Spread on Variable Rate			1.75%	0.75%	0.75%	0.75%
Leverage Ratio, Total			1.0	1.0	1.0	1.0
Maximum
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity										$ 175,000,000
Debt Instrument, Basis Spread on Variable Rate			2.75%	1.75%	1.75%	1.75%
Leverage Ratio, Total			4.0	4.0	4.0	4.0
Federal Funds Purchased
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			0.50%	0.50%	0.50%	0.50%
London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			1.00%	1.00%	1.00%	1.00%
London Interbank Offered Rate (LIBOR) \| Minimum
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			2.75%	1.75%	1.75%	1.75%
London Interbank Offered Rate (LIBOR) \| Maximum
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate			3.75%	2.75%	2.75%	2.75%
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity						$ 500,000,000
Line of Credit Facility, Expiration Period	5 years
Revolving Credit Facility \| Minimum
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 425,000,000
Revolving Credit Facility \| Maximum
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,000,000,000