Represents loan origination cost net of amortization.

No definition available.

Name:	res_LoanOriginationCostNetOfAmortization
Namespace Prefix:	res_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents maximum consolidated leverage ratio.

+ References

No definition available.

+ Details

Name:	res_MaximumConsolidatedLeverageRatio
Namespace Prefix:	res_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents minimum debt service coverage ratio.

+ References

No definition available.

+ Details

Name:	res_MinimumDebtServiceCoverageRatio
Namespace Prefix:	res_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of minimum EBITDA.

+ References

No definition available.

+ Details

Name:	res_MinimumEbitda
Namespace Prefix:	res_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the number of additional credit lenders in addition to Bank of America.

+ References

No definition available.

+ Details

Name:	res_NumberOfAdditionalCreditLenders
Namespace Prefix:	res_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents reduction in commitment fees payable percentage.

+ References

No definition available.

+ Details

Name:	res_ReductionInCommitmentFeesPayablePercentage
Namespace Prefix:	res_
Data Type:	num:percentItemType
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

Amount of the fee that accompanies borrowing money under the debt instrument.

+ 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(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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

- Definition

The lowest amount of net worth (total assets minus total liabilities) required by secondary market investors or state-imposed regulatory mandates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47080-110998

+ Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=res_AmendmentMember
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:

- 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_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_VariableRateAxis=us-gaap_FederalFundsEffectiveSwapRateMember
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Balance Type:
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Name:	us-gaap_VariableRateAxis=us-gaap_EurodollarMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=res_SwinglineFacilityMember
Namespace Prefix:
Data Type:	na
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NOTES PAYABLE TO BANKS - Credit Facility (Details) $ in Thousands		6 Months Ended
	Jul. 26, 2018 USD ($)	Jun. 30, 2019 USD ($) Lender	Dec. 31, 2018 USD ($)
Amendment
Revolving credit facility
Maximum consolidated leverage ratio	2.50%
Minimum Debt Service Coverage Ratio	2.00%
Minimum EBITDA	$ 50,000
Minimum net worth covenant	$ 600,000
Revolving credit facility
Revolving credit facility
Number of additional credit lenders \| Lender		5
Maximum borrowing capacity		$ 125,000
Origination and other costs		3,300
Unamortized origination and other costs		300
Outstanding debt		0
Remaining borrowing capacity		$ 104,400
Revolving credit facility \| Minimum
Revolving credit facility
Annual fee (as a percent)		0.15%
Revolving credit facility \| Maximum
Revolving credit facility
Annual fee (as a percent)		0.25%
Revolving credit facility \| Amendment
Revolving credit facility
Reduction in commitment fees (in points)	7.50%
Revolving credit facility \| Amendment \| Eurodollar Rate \| LIBOR \| Minimum
Revolving credit facility
Basis points added		1.125%
Revolving credit facility \| Amendment \| Eurodollar Rate \| LIBOR \| Maximum
Revolving credit facility
Basis points added		2.125%
Revolving credit facility \| Amendment \| Base Rate \| Minimum
Revolving credit facility
Basis points added		0.125%
Revolving credit facility \| Amendment \| Base Rate \| Maximum
Revolving credit facility
Basis points added		1.125%
Revolving credit facility \| Amendment \| Base Rate \| Federal Funds Rate
Revolving credit facility
Basis points added		0.50%
Revolving credit facility \| Amendment \| Base Rate \| Eurodollar Rate
Revolving credit facility
Basis points added		1.00%
Revolving credit facility \| Letter of credit
Revolving credit facility
Maximum borrowing capacity		$ 35,000	$ 50,000
Outstanding debt		20,600
Revolving credit facility \| Letter of credit \| Amendment
Revolving credit facility
Maximum borrowing capacity	$ 35,000
Revolving credit facility \| Swingline
Revolving credit facility
Maximum borrowing capacity		$ 35,000