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Summary of Significant Accounting Policies - Revenue by Major Payers (Details) - Customer Concentration Risk	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Medicare | Revenue Benchmark
Disaggregation of Revenue [Line Items]
Percent of total revenue		20.00%	25.00%
Janssen (SIMPONI) | Revenue Benchmark
Disaggregation of Revenue [Line Items]
Percent of total revenue		12.00%
Janssen (SIMPONI) | Accounts Receivable
Disaggregation of Revenue [Line Items]
Percent of total revenue		35.00%	19.00%
Blue Shield | Revenue Benchmark
Disaggregation of Revenue [Line Items]
Percent of total revenue		11.00%	12.00%
Blue Shield | Accounts Receivable
Disaggregation of Revenue [Line Items]
Percent of total revenue	15.00%	11.00%
Medicare Advantage | Revenue Benchmark
Disaggregation of Revenue [Line Items]
Percent of total revenue		11.00%	11.00%
United Healthcare | Revenue Benchmark
Disaggregation of Revenue [Line Items]
Percent of total revenue			11.00%
United Healthcare | Accounts Receivable
Disaggregation of Revenue [Line Items]
Percent of total revenue	22.00%

X

- 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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