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Data Type:	xbrli:stringItemType
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- References

No definition available.

Name:	pre_CommonSharesAbstract
Namespace Prefix:	pre_
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Percentage Ownership

No definition available.

Name:	pre_PercentageOwnership
Namespace Prefix:	pre_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Special dividend per share paid or expected to be paid to common stockholders as a result of a business combination.

No definition available.

Name:	pre_SpecialDividendPerSharePaid
Namespace Prefix:	pre_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

No definition available.

Name:	us-gaap_BusinessAcquisitionSharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
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Face amount or stated value per share of common stock.

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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Value of all classes of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares exclude common shares repurchased by the entity and held as treasury shares.