GOODWILL AND OTHER INTANGIBLE ASSETS (Details - Annual Amortization Schedule) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)
Finite-Lived Intangible Assets [Line Items]
Amortization year 2021	$ 3,630
Amortization year 2022	3,498
Amortization year 2023	3,236
Amortization year 2024	2,818
Amortization year 2025	2,584
Amortization year thereafter	36,627
Amortiztion total	52,393
Management Service Contracts
Finite-Lived Intangible Assets [Line Items]
Amortization year 2021	2,287
Amortization year 2022	2,287
Amortization year 2023	2,287
Amortization year 2024	2,287
Amortization year 2025	2,287
Amortization year thereafter	13,533
Amortiztion total	$ 24,968
Weighted average amortization period remaining in years	10 years 10 months 24 days
Covenant not to compete and other contracts
Finite-Lived Intangible Assets [Line Items]
Amortization year 2021	$ 1,024
Amortization year 2022	994
Amortization year 2023	883
Amortization year 2024	467
Amortization year 2025	233
Amortization year thereafter	0
Amortiztion total	$ 3,601
Weighted average amortization period remaining in years	3 years 10 months 24 days
Developed Technology
Finite-Lived Intangible Assets [Line Items]
Amortization year 2021	$ 244
Amortization year 2022	142
Amortization year 2023	0
Amortization year 2024	0
Amortization year 2025	0
Amortization year thereafter	0
Amortiztion total	$ 386
Weighted average amortization period remaining in years	1 year 7 months 6 days
Trade Names amortized
Finite-Lived Intangible Assets [Line Items]
Amortization year 2021	$ 75
Amortization year 2022	75
Amortization year 2023	66
Amortization year 2024	64
Amortization year 2025	64
Amortization year thereafter	309
Amortiztion total	$ 653
Weighted average amortization period remaining in years	5 years 4 months 24 days
Trade Names indefinite life
Finite-Lived Intangible Assets [Line Items]
Amortization year 2021	$ 0
Amortization year 2022	0
Amortization year 2023	0
Amortization year 2024	0
Amortization year 2025	0
Amortization year thereafter	7,100
Amortiztion total	7,100
Software in development
Finite-Lived Intangible Assets [Line Items]
Amortization year 2021	0
Amortization year 2022	0
Amortization year 2023	0
Amortization year 2024	0
Amortization year 2025	0
Amortization year thereafter	15,685
Amortiztion total	$ 15,685
Weighted average amortization period remaining in years	0 years

Weighted average amortization period remaining in years

No definition available.

Name:	rdnt_WeightedAverageAmortizationPeriodRemainingInYears
Namespace Prefix:	rdnt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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

- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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

- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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

- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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

- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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

- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_FiniteLivedIntangibleAssetsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120154696&loc=d3e54445-107959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=rdnt_ManagementServiceContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=rdnt_CovenantNotToCompeteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=rdnt_DevelopedtechnologyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=rdnt_TradeNamesAmortizedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=rdnt_TradeNamesIndefiniteLifeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_SoftwareDevelopmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: