Name:	pkg_AllowanceForDoubtfulAccountsReceivableAndReserveForCustomerDeductionsCurrent
Namespace Prefix:	pkg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Short-Term Marketable Debt Securities

No definition available.

Name:	pkg_ShortTermMarketableDebtSecurities
Namespace Prefix:	pkg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Face amount or stated value per share of common stock.

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(16)(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1

Name:	us-gaap_CommonStockSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

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.

Name:	us-gaap_CommonStockSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.