Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
	Feb. 29, 2016	Mar. 31, 2016	Dec. 31, 2015
Accounting Policies [Line Items]
Fair value of liabilities on recurring basis		$ 0	$ 0
Fair value, assets transfers from Level 1 to Level 2 measurement		0
Fair value, assets transfers from Level 2 to Level 1 measurement		0
Fair Value, assets transfers into (out of) Level 3 measurement		$ 0
Maximum maturity days for cash equivalents		90 days
Nestlé Health Science [Member]
Accounting Policies [Line Items]
Upfront non-refundable payment	$ 120,000,000	$ 120,000,000