Business (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	1 Months Ended
Sep. 30, 2011	Oct. 31, 2011 Portola Pharmaceuticals Inc. [Member] Collaborative Arrangement, Co-promotion [Member]	Oct. 31, 2011 Collaborative Arrangement, Co-promotion [Member]
Subsequent Event [Line Items]
Upfront Payment		$ 36.0
Remaining potential development milestone payments and royalties on commercial sales under the terms of collaboration agreement		508.5
Percentage of expenses shared and profit shared		25.00%	75.00%
Percentage of co-promote arrangement		25.00%
Equity investment		$ 9.0
Business (Textuals) [Abstract]
Interest in subsidiary (less than given percentage)	100.00%
Percentage of operations of joint venture investments on financial statements	100.00%
Percentage of net income (loss) attributable to noncontrolling interests	50.00%

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Interest in subsidiary.

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License agreement percentage of co promote arrangement maximum.

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Net income loss attributable to noncontrolling interest percentage.

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Percentage of operations from joint-venture investments reflected in the consolidated financial statements.

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Percentage share of development and commercialization expenses and profits.

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Expected total payments including upfront and milestone payments as well as the greater of an annual maintenance fee or usage-based royalty payments under the terms of collaboration agreement.

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Total upfront and reimbursement payment made to collaborative partner.

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Value of preferred shares purchased.

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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.

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