Business Acquisition - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
Dec. 31, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Business acquisition upfront cash payments		$ 5,000,000
Business combination, goodwill	10,000,000us-gaap_Goodwill	10,000,000us-gaap_Goodwill
CureTech Ltd [Member]
Business Acquisition [Line Items]
Business acquisition upfront cash payments	5,000,000	5,000,000
Milestone payment	5,000,000
Acquisition-date fair value of contingent consideration payments	106,000,000	106,000,000
Business combination, identifiable intangible asset	101,000,000	101,000,000
Business combination, goodwill	10,000,000	10,000,000
Business combination, Goodwill expected to be deductible for tax purposes	10,000,000	10,000,000
Minimum [Member] \| CureTech Ltd [Member]
Business Acquisition [Line Items]
Percentage of royalty	5.00%	5.00%
Maximum [Member] \| CureTech Ltd [Member]
Business Acquisition [Line Items]
Percentage of royalty	11.00%	11.00%
Sales milestones earned [Member] \| CureTech Ltd [Member]
Business Acquisition [Line Items]
Business acquisition maximum contingent consideration	85,000,000	85,000,000
Development milestones earned [Member] \| CureTech Ltd [Member]
Business Acquisition [Line Items]
Business acquisition maximum contingent consideration	$ 245,000,000	$ 245,000,000

Dollar amount of future milestone payment for Technology transfer under manufacturing services agreement.

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- Definition

Range of percentage rates for royalties paid annual worldwide net sales, as defined by license agreement.

+ References

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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