v3.5.0.2

Development and Other Agreements - Additional Information (Detail) - USD ($)	1 Months Ended			3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Jul. 31, 2014	Feb. 29, 2012	Sep. 30, 2015	Sep. 30, 2016	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

X

- Definition

Collaborative Arrangement, Additional milestone payments.

+ References

No definition available.

+ Details

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- Definition

Collaborative Arrangement, Commitment Amount, Royalty Eligible Sales Threshold Not Achieved

+ References

No definition available.

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- Definition

Collaborative Arrangement, Development & Regulatory Milestones

+ References

No definition available.

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- Definition

Collaborative Arrangement, Marketing Funds per Product Sold

+ References

No definition available.

+ Details

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- Definition

Collaborative Arrangement, One Time Milestone Payment, Received

+ References

No definition available.

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- Definition

Collaborative Arrangement, Royalty Eligible Sales

+ References

No definition available.

+ Details

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- Definition

Collaborative Arrangement, Royalty per Product Sold

+ References

No definition available.

+ Details

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- Definition

Collaborative Arrangement, Third Party Contribution To Off Set Expenses

+ References

No definition available.

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- Definition

Collaborative Arrangement, Upfront Fee

+ References

No definition available.

+ Details

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X

- Definition

Development Agreements [Line Items]

+ References

No definition available.

+ Details

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X

- Definition

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23199-108380

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23221-108380

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X

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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X

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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