XML 56 R46.htm IDEA: XBRL DOCUMENT v3.8.0.1

Subsequent Event (Details) - Subsequent Event [Member] $ / shares in Units, $ in Millions	Oct. 16, 2017 USD ($) $ / shares shares
S-3 Offering [Member]
Subsequent Event [Line Items]
Number of shares Issued in transaction | shares	3,530,000
Sale of stock, price per share | $ / shares	$ 17.00
Consideration received on transaction, gross | $	$ 60.0
Consideration received on transaction | $	$ 56.2
Over-Allotment Option [Member]
Subsequent Event [Line Items]
Number of shares Issued in transaction | shares	529,500

X

- Definition

Sale of Stock, Consideration Received on Transaction, Gross

+ References

No definition available.

+ Details

Name:	ptgx_SaleofStockConsiderationReceivedonTransactionGross
Namespace Prefix:	ptgx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockConsiderationReceivedOnTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=ptgx_S3OfferingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_OverAllotmentOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: