Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

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-Topic 230
-SubTopic 10
-Section 45
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Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_DebtInstrumentAxis=rngr_SellersNotesMember
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Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=rngr_SellerSNoteDueAugust2018Member
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- Details

Name:	us-gaap_DebtInstrumentAxis=rngr_SellerSNoteDueFebruary2019Member
Namespace Prefix:
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Period Type:

Debt - ESCO Notes Payable (Details) - USD ($)	12 Months Ended
Debt - ESCO Notes Payable (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 16, 2017
Debt Instrument [Line Items]
Gain on debt retirement	$ 2,100,000	$ 0
ESCO Notes Payable
Debt Instrument [Line Items]
Extinguishment of debt, amount			$ 5,800,000
Payment for retirement of debt	3,800,000
Gain on debt retirement	$ 2,100,000
Seller's Notes
Debt Instrument [Line Items]
Face amount of debt				$ 7,000,000.0
Interest rate (as a percent)				5.00%
Seller's Note Due August 2018
Debt Instrument [Line Items]
Face amount of debt				$ 1,200,000
Seller's Note Due February 2019
Debt Instrument [Line Items]
Face amount of debt				$ 5,800,000