Primary sources of revenue description.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

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-Publisher FASB
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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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-Publisher FASB
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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

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- 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.

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Revenue and Accounts Receivable Credit Concentration - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Disaggregation Of Revenue [Line Items]
Primary sources of revenue, description			We derive our revenue from two primary sources: (i) providing diagnostic testing in the clinical setting (Diagnostic Tests); and (ii) providing biopharmaceutical companies with services that include diagnostic research, clinical research, clinical trial testing, development and testing services generally provided outside the clinical setting and governed by individual contracts with third parties as well as development and commercialization of companion diagnostics (Services).
Revenue recognized					$ 2,700
Deferred revenue	$ 1,760		$ 1,760		3,532
Revenue \| Minimum \| Customer Concentration Risk
Disaggregation Of Revenue [Line Items]
Concentration risk, percentage	10.00%	26.00%	53.00%	19.00%
Revenue \| Minimum \| Customer Concentration Risk \| Medicare
Disaggregation Of Revenue [Line Items]
Concentration risk, percentage	36.00%	63.00%	14.00%	61.00%
Up Front Cash Payments
Disaggregation Of Revenue [Line Items]
Deferred revenue	$ 1,000		$ 1,000
Other Long-term Liabilities
Disaggregation Of Revenue [Line Items]
Non-current deferred revenue	$ 1,000		$ 1,000		$ 1,400