Revenue Recognition - Additional Information (Detail) - USD ($)	1 Months Ended				3 Months Ended
	Oct. 31, 2016	Mar. 31, 2016	Feb. 29, 2016	Jul. 31, 2014	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Costs to obtain or fulfill the contract capitalized					$ 0
Collaboration and license revenue (reversal of revenue)					26,389,000	$ 22,169,000
Contract liabilities					4,896,000		$ 5,518,000
Unbilled - collaboration and license revenue					3,408,000		3,783,000
Deferred revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contract liabilities							$ 5,518,000
2016 Agreement | BMS and Pfizer
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Non-refundable upfront fee			$ 15,000,000.0
Contingent payment receivable upon achievement of regulatory events			20,000,000.0
Contingent payment receivable upon achievement of annual net sales volumes			$ 70,000,000.0
2016 Agreement | BMS and Pfizer | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Transaction price					10,800,000
Upfront payment					15,000,000.0
2016 Agreement | BMS and Pfizer | Topic 606 | Accounting Standards Update 2014-09 | Deferred revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contract liabilities					4,300,000
2016 Agreement | BMS and Pfizer | Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of royalties entitle to receive under agreement			5.00%
2016 Agreement | BMS and Pfizer | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of royalties entitle to receive under agreement			15.00%
2016 Agreement | Daiichi Sankyo, Inc ("Daiichi") | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Costs to obtain or fulfill the contract capitalized					0
Transaction price					16,300,000
Upfront payment					5,000,000.0
Estimated variable consideration transaction price					6,800,000
Regulatory milestone payments					10,000,000.0
2016 Agreement | Daiichi Sankyo, Inc ("Daiichi") | Topic 606 | Accounting Standards Update 2014-09 | Ethnic Sensitivity Study
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Estimated variable consideration transaction price					4,500,000
2016 Agreement | Daiichi Sankyo, Inc ("Daiichi") | Topic 606 | Accounting Standards Update 2014-09 | Deferred revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Unbilled - collaboration and license revenue					1,500,000
2016 Agreement | Bayer Pharma AG
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront fee			$ 5,000,000.0
Contingent payment receivable upon achievement			10,000,000.0
Reduced contingent payment receivable upon achievement			$ 7,000,000.0
2016 Agreement | Bayer Pharma AG | Ethnic Sensitivity Study
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Reimbursement of costs and expenses percentage			33.00%
2016 Agreement | Bayer Pharma AG | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Transaction price					16,300,000
Upfront payment					5,000,000.0
Milestone payments eligible for achievement					10,000,000.0
Costs to obtain or fulfill the contract					0
Estimated variable consideration transaction price					6,800,000
Unbilled - collaboration and license revenue					2,000,000.0
2016 Agreement | Bayer Pharma AG | Topic 606 | Accounting Standards Update 2014-09 | Ethnic Sensitivity Study
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Estimated variable consideration transaction price					4,500,000
2016 Agreement | Bayer Pharma AG | Minimum | Rivaroxaban
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Reimbursement of costs and expenses percentage			33.00%
2016 Agreement | Bayer Pharma AG | Maximum | Rivaroxaban
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Reimbursement of costs and expenses percentage			100.00%
2014 Agreement | Daiichi Sankyo, Inc ("Daiichi")
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront fee				$ 15,000,000.0
Contingent payment receivable upon achievement				5,000,000.0
Milestone payments of development and regulatory event				$ 20,000,000.0
2014 Agreement | Bayer Pharma, AG ('Bayer") and Janssen Pharmaceuticals, Inc. ("Janssen") | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Costs to obtain or fulfill the contract capitalized					0
October 2016 Agreement | Daiichi Sankyo, Inc ("Daiichi")
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contingent payment receivable upon achievement of annual net sales volumes	$ 8,000,000.0
Upfront fee	15,000,000.0
Contingent payment receivable upon achievement	10,000,000.0
Milestone payments of development and regulatory event	$ 2,500,000
Percentage of consideration received under agreement	1.00%
March 2016 Agreement | Daiichi Sankyo, Inc ("Daiichi") | Ethnic Sensitivity Study
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Reimbursement of costs and expenses percentage		33.00%
March 2016 Agreement | Daiichi Sankyo, Inc ("Daiichi") | Minimum | Edoxaban
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Reimbursement of costs and expenses percentage		33.00%
March 2016 Agreement | Daiichi Sankyo, Inc ("Daiichi") | Maximum | Edoxaban
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Reimbursement of costs and expenses percentage		100.00%
2014 Agreement and October 2016 Amendment | Daiichi Sankyo, Inc ("Daiichi") | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Transaction price					34,000,000.0
Upfront payment					22,000,000.0
Milestones already received on achieving performance obligations					12,000,000.0
Milestone payments eligible for achievement					5,500,000
Costs to obtain or fulfill the contract					0
2014 Agreement and October 2016 Amendment | Daiichi Sankyo, Inc ("Daiichi") | Topic 606 | Accounting Standards Update 2014-09 | Deferred revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contract liabilities					600,000
Distribution Fees and Reserves for Cargebacks and Product Returns
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Reduction to revenue					5,200,000	2,400,000
Royalty
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration and license revenue (reversal of revenue)					0
Collaboration and license revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration and license revenue (reversal of revenue)					752,000	$ 1,807,000
Collaboration and license revenue | 2016 Agreement | BMS and Pfizer | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration and license revenue (reversal of revenue)					(300,000)
Collaboration and license revenue | 2016 Agreement | Daiichi Sankyo, Inc ("Daiichi") | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration and license revenue (reversal of revenue)					300,000
Collaboration and license revenue | 2016 Agreement | Bayer Pharma AG | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration and license revenue (reversal of revenue)					100,000
Collaboration and license revenue | 2014 Agreement and October 2016 Amendment | Daiichi Sankyo, Inc ("Daiichi") | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration and license revenue (reversal of revenue)					100,000
New Drug Application | 2016 Agreement | BMS and Pfizer | Topic 606 | Accounting Standards Update 2014-09
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Estimated variable consideration transaction price					4,300,000
New Drug Application | 2016 Agreement | BMS and Pfizer | Topic 606 | Accounting Standards Update 2014-09 | Japan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payment					5,000,000.0
Phase Four Clinical Trial | 2016 Agreement | BMS and Pfizer | Topic 606 | Accounting Standards Update 2014-09 | Japan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Costs on clinical trial					600,000
Decrease in transaction price					$ 14,100,000