Concentrations and Credit Risks (Details)	12 Months Ended
Dec. 31, 2019 item customer	Dec. 31, 2018 item customer
Purchases \| Supplier concentration risk
Concentrations and Credit Risk
Number of suppliers \| item	3	4
Purchases \| Supplier concentration risk \| Minimum
Concentrations and Credit Risk
Concentration risk (as a percent)	92.00%	96.00%
Product Revenue \| Gross Sales \| Customer concentration risk
Concentrations and Credit Risk
Number of customers \| customer	3	3
Concentration risk (as a percent)	97.00%	96.00%
Product Revenue \| Gross Sales \| Customer concentration risk \| Amerisource Bergen
Concentrations and Credit Risk
Concentration risk (as a percent)	12.00%	7.00%
Product Revenue \| Gross Sales \| Customer concentration risk \| Cardinal Health
Concentrations and Credit Risk
Concentration risk (as a percent)	47.00%	55.00%
Product Revenue \| Gross Sales \| Customer concentration risk \| McKesson
Concentrations and Credit Risk
Concentration risk (as a percent)	38.00%	34.00%
Product Revenue \| Gross Sales \| Product Concentration Risk [Member]
Concentrations and Credit Risk
Concentration risk (as a percent)	57.00%	66.00%
Number of products \| item	1	1
Product Revenue \| Gross Accounts Receivable \| Customer concentration risk
Concentrations and Credit Risk
Number of customers \| customer	3	3
Concentration risk (as a percent)	94.00%	96.00%
Product Revenue \| Gross Accounts Receivable \| Customer concentration risk \| Amerisource Bergen
Concentrations and Credit Risk
Concentration risk (as a percent)	21.00%	6.00%
Product Revenue \| Gross Accounts Receivable \| Customer concentration risk \| Cardinal Health
Concentrations and Credit Risk
Concentration risk (as a percent)	22.00%	61.00%
Product Revenue \| Gross Accounts Receivable \| Customer concentration risk \| McKesson
Concentrations and Credit Risk
Concentration risk (as a percent)	51.00%	29.00%
Royalty Revenue \| Gross Sales \| Customer concentration risk
Concentrations and Credit Risk
Concentration risk (as a percent)	78.00%	67.00%
Royalty Revenue \| Gross Sales \| Customer concentration risk \| Customer 4 [Member]
Concentrations and Credit Risk
Concentration risk (as a percent)	75.00%	36.00%
Royalty Revenue \| Gross Sales \| Customer concentration risk \| Customer 5 [Member]
Concentrations and Credit Risk
Concentration risk (as a percent)	3.00%	31.00%
Royalty Revenue \| Gross Accounts Receivable \| Customer concentration risk
Concentrations and Credit Risk
Concentration risk (as a percent)	93.00%	73.00%
Royalty Revenue \| Gross Accounts Receivable \| Customer concentration risk \| Customer 4 [Member]
Concentrations and Credit Risk
Concentration risk (as a percent)	93.00%	43.00%
Royalty Revenue \| Gross Accounts Receivable \| Customer concentration risk \| Customer 5 [Member]
Concentrations and Credit Risk
Concentration risk (as a percent)		30.00%

Represents the number of customers representing the concentration of risk.

No definition available.

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- Definition

The number of products contributing to the concentration of risk.

+ References

No definition available.

+ Details

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- Definition

The number of suppliers contributing to the concentration of risk.

+ References

No definition available.

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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.

+ Details

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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