Other Intangible Assets - Schedule of Identifiable Intangible Assets Carrying Value (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Finite-lived Intangible Assets, Accumulated Amortization	$ (14,580)	$ (13,767)
Finite-lived Intangible Assets, Net Carrying Value	$ 29,040	$ 29,853
Diagnostic Assets, Thyroid [Member] \| Asuragen Acquisition [Member]
Finite-lived Intangible Asset, Useful Life (Years)	9 years	9 years
Finite-lived Intangible Assets, Gross	$ 8,519	$ 8,519
Diagnostic Assets, Pancreas Test [Member] \| RedPath Acquisition [Member]
Finite-lived Intangible Asset, Useful Life (Years)	7 years	7 years
Finite-lived Intangible Assets, Gross	$ 16,141	$ 16,141
Diagnostic Assets, Barrett's Test [Member] \| RedPath Acquisition [Member]
Finite-lived Intangible Asset, Useful Life (Years)	9 years	9 years
Finite-lived Intangible Assets, Gross	$ 18,351	$ 18,351
Diagnostic Lab, CLIA Lab [Member]
Finite-lived Intangible Asset, Useful Life (Years)	2 years 3 months 19 days	2 years 3 months 19 days
Finite-lived Intangible Assets, Gross	$ 609	$ 609
Diagnostic Assets [Member]
Finite-lived Intangible Assets, Gross	$ 43,011	$ 43,011

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.

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- 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/disclosureRef
-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

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- Definition

Amount before 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 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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

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- Definition

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

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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