SUBSEQUENT EVENT (Detail Textuals) - Subsequent Event	1 Months Ended
Oct. 24, 2017 $ / shares
Subsequent Event [Line Items]
Dividends payable, date declared	Oct. 24, 2017
Cash dividend payable (in dollars per share)	$ 0.07
Special dividend payable (in dollars per share)	$ 0.07
Dividends payable date	Dec. 11, 2017
Dividends payable, record date	Nov. 10, 2017

The per share amount of a special dividend.

No definition available.

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Namespace Prefix:	res_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

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Period Type:	duration

- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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