Outstanding Performance Share Units Awarded (Parenthetical) (Detail) - Performance share units	9 Months Ended
Sep. 30, 2015 shares
Year of Award 2013 \| Brigatinib clinical trial enrollment
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percent dependent upon achievement of specific commercial objectives	100.00%
Year of Award 2014 \| Iclusig clinical trial enrollment
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percent dependent upon achievement of specific commercial objectives	50.00%
Year of Award 2014 \| cumulative 2 year revenues from sales of Iclusig
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percent dependent upon achievement of specific commercial objectives	50.00%
Year of Award 2015 \| Iclusig clinical trial enrollment
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units vested upon milestone achievement	315,000
Year of Award 2015 \| 2015 revenues from sales of Iclusig
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units vested upon milestone achievement	315,000
Year of Award 2015 \| total relative return on common stock 2015-2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units vested upon milestone achievement	101,300
Year of Award 2015 \| total relative return on common stock 2015-2017 \| Measurement start Year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total relative return on common stock, measuring year for milestone	2015
Year of Award 2015 \| total relative return on common stock 2015-2017 \| Measurement end Year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total relative return on common stock, measuring year for milestone	2017

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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