Share-Based Compensation - Share Based Compensation Expense By Type (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-Based Compensation
Share-based compensation expense	$ 51,313	$ 49,145	$ 41,169
Unrecognized compensation cost	86,855
Options
Share-Based Compensation
Share-based compensation expense	8,441	7,969	7,591
Unrecognized compensation cost	$ 18,147
Weighted-average amortization period - years	2 years 10 months 2 days
RSUs
Share-Based Compensation
Share-based compensation expense	$ 34,077	25,959	20,946
Unrecognized compensation cost	$ 62,718
Weighted-average amortization period - years	2 years 5 months 27 days
Performance-Contingent Awards - RSAs and RSUs
Share-Based Compensation
Share-based compensation expense	$ 4,707	9,224	1,808
Unrecognized compensation cost	$ 3,604
Weighted-average amortization period - years	1 year 1 month 21 days
ESPP
Share-Based Compensation
Share-based compensation expense	$ 3,351	2,135	1,702
Unrecognized compensation cost	$ 2,322
Weighted-average amortization period - years	1 year 11 days
Innoviva \| Options
Share-Based Compensation
Share-based compensation expense	$ 280	2,973	3,973
Unrecognized compensation cost	$ 0
Weighted-average amortization period - years	0 years
Innoviva \| RSUs
Share-Based Compensation
Share-based compensation expense	$ 0	224	1,547
Innoviva \| RSAs
Share-Based Compensation
Share-based compensation expense	457	660	2,597
Unrecognized compensation cost	$ 64
Weighted-average amortization period - years	2 months 23 days
Innoviva \| Performance-Contingent Awards - RSAs
Share-Based Compensation
Share-based compensation expense	$ 0	$ 1	$ 1,005

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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No definition available.

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