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Collaboration Agreements and Revenues - Product Revenue - Additional Information 5 (Detail) - Astellas Agreement [Member] - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2018 | Jun. 30, 2018 | Dec. 31, 2019 | Dec. 31, 2018
Japan [Member] |  |  |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |  |  |
Contract with customer, liability, revenue recognized | $ 43.9 | $ 20.9 |  |
Product Revenue [Member] | Japan [Member] |  |  |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |  |  |
Contract with customer, liability, revenue recognized |  |  |  | $ 64.8
Change in estimated variable consideration |  |  | $ 36.3 |
Roxadustat Drug [Member] | China [Member] |  |  |  |
Revenue Recognition, Multiple-deliverable Arrangements [Line Items] |  |  |  |
Amount adjusted based on government listed price and estimated channel inventory levels |  |  | $ 0.9 |

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- Definition Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130551-203045 + Details
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