Employee Benefit Plans - Stock Options (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Options
Stock incentive plans
Minimum ownership considered major owner	10.00%
Percentage of fair market value of the common stock for major owners	110.00%
Vesting period	5 years
Expiration period of the stock	10 years
Expiration period of the stock of majority owners	5 years
Restricted Stock
Stock incentive plans
Stock based compensation award, vesting percentage	20.00%
Weighted average grant date fair value (in dollars per share)	$ 4.59	$ 11.39	$ 25.13
Total fair value of shares vested	$ 3,474,000	$ 7,026,000	$ 16,483,000
Tax benefits for compensation expense for restricted stock awards	0	$ 442,000
Unrecognized compensation cost related to non-vested restricted shares	$ 40,891,000
Period for recognition of compensation cost related to non-vested restricted shares	3 years 9 months 18 days

This element represents the minimum threshold limit percentage of incentive stock option grants to owners.

No definition available.

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

- Definition

This element represents the percentage of fair market value of the common stock.

+ References

No definition available.

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- Definition

This element represents the share based compensation arrangement by share based payment award expirations in period of majority owner.

+ References

No definition available.

+ Details

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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Period Type:	instant

- Definition

Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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-Publisher FASB
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-SubTopic 10
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
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-Paragraph 2
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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- 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

Percentage of vesting of award under share-based payment arrangement.

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-Publisher FASB
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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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