Strategic Collaborations and Other Significant Agreements - Deferred Revenues Balance (Details) $ in Thousands	Jun. 30, 2018 USD ($)
Deferred revenue:
Short-Term	$ 78,613
Long-Term	80,890
Total	159,503
Otsuka Pharmaceutical Company. Ltd. \| U.S.
Deferred revenue:
Short-Term	46,151
Long-Term	43,980
Total	90,131
Otsuka Pharmaceutical Company. Ltd. \| International
Deferred revenue:
Short-Term	32,462
Long-Term	32,231
Total	64,693
Vifor Pharma
Deferred revenue:
Long-Term	4,679
Total	$ 4,679

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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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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