Note 4 - Other Intangible Assets - Identifiable Intangible Assets Carrying Value (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Diagnostic Test, Thyroid [Member] \| Asuragen [Member]
Finite-lived intangible asset, useful life	9 years
Finite-Lived Intangible Assets, Net	$ 8,519	$ 8,519
Diagnostic Test, Pancreas [Member] \| Asuragen [Member]
Finite-lived intangible asset, useful life
Finite-Lived Intangible Assets, Net		2,882
Diagnostic Test, Pancreas [Member] \| RedPath [Member]
Finite-lived intangible asset, useful life	7 years
Finite-Lived Intangible Assets, Net	$ 16,141	16,141
Diagnostic Test, Biobank [Member] \| Asuragen [Member]
Finite-lived intangible asset, useful life
Finite-Lived Intangible Assets, Net		1,575
Diagnostic Test, Barrett's RedPath [Member] \| RedPath [Member]
Finite-lived intangible asset, useful life	9 years
Finite-Lived Intangible Assets, Net	$ 18,351	18,351
CLIA Diagnostic Lab [Member]
Finite-lived intangible asset, useful life	2 years 109 days
Finite-Lived Intangible Assets, Net	$ 609	609
RedPath [Member]
Finite-Lived Intangible Assets, Net	43,011	47,468
Finite-Lived Intangible Assets, Net	37,220	43,492
Finite-Lived Intangible Assets, Accumulated Amortization	$ (6,400)	$ (4,585)

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

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Period Type:	instant

- Definition

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

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=idxg_DiagnosticTestBiobankMember
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- Details

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- Details

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