Subsequent Events - Additional Information (Detail) - HealthCare Royalty Partners (“HCRP”) - Andexanet Alfa - Subsequent Event	1 Months Ended
	Feb. 28, 2017 USD ($)
Subsequent Event [Line Items]
Royalty interest amount received on closing of agreement	$ 50,000,000
Additional amount receivable upon U.S. regulatory approval	$ 100,000,000
Scenario One
Subsequent Event [Line Items]
Percentage of royalty obligated to pay of net worldwide sales	2.00%
Target payment for royalty obligation	$ 50,000,000
Scenario Two
Subsequent Event [Line Items]
Target payment for royalty obligation	$ 150,000,000
Scenario Two | Maximum
Subsequent Event [Line Items]
Percentage of royalty obligated to pay of net worldwide sales	7.85%
Scenario Two | Minimum
Subsequent Event [Line Items]
Percentage of royalty obligated to pay of net worldwide sales	3.58%
Scenario Three
Subsequent Event [Line Items]
Percentage of royalty obligated to pay of net worldwide sales	195.00%
Scenario Three | Minimum
Subsequent Event [Line Items]
Target payment for royalty obligation	$ 150,000,000