Number of consecutive trading period.

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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Period Type:

Subsequent Events - Additional Information (Detail) (USD $)	12 Months Ended		1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Jan. 31, 2015
Subsequent Event [Line Items]
Vesting period of stock options	2 years 9 months 18 days	4 years
Subsequent
Subsequent Event [Line Items]
Vesting period of stock options			4 years
Executive officers (PSU) awards			The Compensation Committee of the Board approved for Portola’s named executive officers performance stock unit (PSU) awards. Each PSU represents a contingent right to receive one share of Issuer’s Common Stock
Subsequent \| First Half Shares
Subsequent Event [Line Items]
Average closing price per share when market is above			50.00
Consecutive trading days			45 days
Subsequent \| Additional Half Shares
Subsequent Event [Line Items]
Average closing price per share when market is above			60
Consecutive trading days			45 days