Note 18 - Subsequent Events (Details Textual) - USD ($) $ in Thousands		9 Months Ended
Oct. 01, 2018	Sep. 29, 2018	Sep. 30, 2017
Payments to Acquire Businesses, Gross		$ 300	$ 800
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		$ 2,400
TKE [Member] \| Subsequent Event [Member]
Business Combination, Consideration Transferred, Total	$ 3,700
Payments to Acquire Businesses, Gross	$ 1,800
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	440,751
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 7,600

Number of shares of equity interests issued or issuable to acquire entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Balance Type:	credit
Period Type:	duration

- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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Period Type:	instant

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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- Details

Name:	us-gaap_BusinessAcquisitionAxis=rcmt_TKEMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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Period Type: