Development and Other Agreements - Additional Information (Detail) - USD ($)	1 Months Ended			3 Months Ended			12 Months Ended
	Sep. 30, 2015	Jul. 31, 2014	Feb. 29, 2012	Mar. 31, 2016	Sep. 30, 2015	Mar. 31, 2015	Dec. 31, 2015	Aug. 10, 2015	Feb. 01, 2012
Helmsley Grant [Member] | Research and Development Grant [Member]
Development Agreements [Line Items]
Research and Development Arrangement, Contract to Perform for Others, Compensation Earned						$ 0
Tandem Diabetes Care, Inc. [Member]
Development Agreements [Line Items]
Royalty per Product Sold (in Dollars per Item)				$ 100
Marketing Funds per Product Sold (in Dollars per Item)				100
Tandem Diabetes Care, Inc. [Member] | Maximum [Member]
Development Agreements [Line Items]
Third party contribution to off set expenses									$ 1,000,000
Tandem Diabetes Care, Inc. [Member] | Initial Payment [Member]
Development Agreements [Line Items]
One-time milestone payment, received			$ 1,000,000
Regulatory Submission Milestone [Member] | Tandem Diabetes Care, Inc. [Member]
Development Agreements [Line Items]
Additional milestone payments		$ 1,000,000
Regulatory Approval Milestone [Member] [Member] | Tandem Diabetes Care, Inc. [Member]
Development Agreements [Line Items]
Additional milestone payments	$ 1,000,000
Google Life Sciences LLC [Member] | Collaborative Arrangement [Member]
Development Agreements [Line Items]
Sales Revenue, Goods, Net				750,000,000
Collaborative Arrangement, Commitment Amount, Royalty Eligible Sales Threshold Not Achieved								$ 0
Google Life Sciences LLC [Member] | Collaborative Arrangement [Member] | Milestone Payments [Member]
Development Agreements [Line Items]
Development & Regulatory Milestone Payments								65,000,000
Google Life Sciences LLC [Member] | Collaborative Arrangement [Member] | Initial Payment [Member]
Development Agreements [Line Items]
Upfront Fee								$ 35,000,000
Shares, Issued					404,591
Share Price								$ 90.29
Research and Development Expense [Member] | Google Life Sciences LLC [Member] | Collaborative Arrangement [Member] | Initial Payment [Member]
Development Agreements [Line Items]
R&D expense through issuance of common stock				$ 36,500,000			$ 36,500,000