Follow on offering price per share.

No definition available.

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- Definition

Initial public offering price per share.

+ References

No definition available.

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- Definition

Proceeds from follow on public offering, gross.

+ References

No definition available.

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- Definition

Proceeds from follow on public offering, net.

+ References

No definition available.

+ Details

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- Definition

Proceeds from issuance of public offering before offering expenses.

+ References

No definition available.

+ Details

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- Definition

Stock issued during period shares existing shareholder.

+ References

No definition available.

+ Details

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- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

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-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

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- Definition

Specific incremental costs directly attributable to a proposed or actual offering of securities which are deferred at the end of the reporting 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 210.5-02.8)

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-Name Accounting Standards Codification

-Topic 340

-SubTopic 10

-Section S99

-Paragraph 1

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section A

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- Definition

Amount of fees and commissions from financial services and banking activities and correspondent clearing. Includes fees from depositor accounts, credit cards, merchant discounts, and fiduciary and trust activities, guarantee fees, investment advisory, management, and administrative fees, transfer agent fees, and insurance commissions.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13)

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 13

-Article 9

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

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- Definition

Cash paid for expenses incurred during underwriting activities (the process to review insurance applications, evaluate risks, accept or reject applications, and determine the premiums to be charged) for insurance companies.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

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- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Topic 230

-SubTopic 10

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-Paragraph 14

-Subparagraph (a)

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- Definition

Number of new stock issued during the period.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Organization - Additional Information (Detail) (USD $)	1 Months Ended			12 Months Ended		1 Months Ended
Organization - Additional Information (Detail) (USD $)	Oct. 31, 2014	Nov. 30, 2013	May 31, 2013	Dec. 31, 2014 Segment	Dec. 31, 2013	Oct. 31, 2013
Organization And Nature Of Business [Line Items]
Number of operating segment				1us-gaap_NumberOfOperatingSegments
Stock issued during the period			9,686,171
Public offering price of the shares sold			$ 14.50ptla_InitialPublicOfferingPricePerShare
Proceeds from initial public offering before offering costs			$ 131,000,000
Underwriting discounts and commissions			9,400,000us-gaap_PaymentsForUnderwritingExpense
Offering expenses	564,000us-gaap_DeferredOfferingCosts		5,200,000us-gaap_DeferredOfferingCosts
Proceeds from initial public offering, net of underwriters discount			125,800,000	175,185,000	251,865,000
Number of preferred stock converted into common stock			24,026,797
Follow on offering price per share	$ 26.00ptla_FollowOnOfferingPricePerShare					23.75ptla_FollowOnOfferingPricePerShare
Proceeds from offering and over-allotment option, gross	175,200,000	120,800,000
Proceeds from offering and over-allotment option, net	174,600,000	119,900,000
Underwriters Overallotment Option
Organization And Nature Of Business [Line Items]
Stock issued during the period	930,000	954,976	1,263,413
Follow-on Offering
Organization And Nature Of Business [Line Items]
Stock issued during the period	6,200,000					6,366,513
Offering expenses		862,000
Stock Issued during period shares existing shareholder						1,908,803
Underwriting discounts and commissions, net	$ 10,200,000	$ 7,700,000