Represents the net income impact from the alternative energy tax credits.

No definition available.

Name:	pkg_AlternativeEnergyTaxCredits
Namespace Prefix:	pkg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
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- Definition

The total amount of tax credits earned for the production and use of alternative fuels in an entity's trade or business.

+ References

No definition available.

+ Details

Name:	pkg_AlternativeFuelMixtureCredits
Namespace Prefix:	pkg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents expenses incurred related to the alternative energy tax credits.

+ References

No definition available.

+ Details

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Namespace Prefix:	pkg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the increase or decrease during the period in the reserve for uncertain tax positions.

+ References

No definition available.

+ Details

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

- Definition

Represents tax credit per gallon of alternative fuel produced.

+ References

No definition available.

+ Details

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

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

+ Details

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

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=pkg_OtherLongTermLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_TaxCreditCarryforwardAxis=pkg_AccruedInterestRelatedtoCellulosicBiofuelTaxCreditsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TaxCreditCarryforwardAxis=pkg_AlternativeEnergyTaxCreditsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TaxCreditCarryforwardAxis=pkg_CellulosicBiofuelTaxCreditsMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_TaxCreditCarryforwardAxis=pkg_TaxRelatedtoCellulosicBiofuelTaxCreditsMember
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Alternative Energy Tax Credits - Additional Information (Detail) (USD $)	12 Months Ended			3 Months Ended		12 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Mar. 31, 2012	Dec. 31, 2010	Dec. 31, 2012	Dec. 31, 2009
Alternative Energy Tax Credits [Line Items]
(Provision) benefit for income taxes	$ (221,700,000)us-gaap_IncomeTaxExpenseBenefit	$ 17,700,000us-gaap_IncomeTaxExpenseBenefit	$ (214,500,000)us-gaap_IncomeTaxExpenseBenefit
Uncertain tax positions						102,000,000
Cellulosic Biofuel Tax Credits
Alternative Energy Tax Credits [Line Items]
Refundable tax credit per gallon								1.01
(Provision) benefit for income taxes				(103,900,000)	(118,500,000)	135,500,000
Alternative Energy Tax Credits
Alternative Energy Tax Credits [Line Items]
Refundable tax credit per gallon								0.50
Alternative energy tax credits					95,500,000	(86,300,000)
(Provision) benefit for income taxes				(62,100,000)
Income (charge) related to alternative energy tax credits			(19,600,000)		(23,000,000)	47,700,000	3,400,000
Alternative Energy Tax Credits \| Additional
Alternative Energy Tax Credits [Line Items]
Expenses related to alternative energy tax credits						1,600,000
Tax Related to Cellulosic Biofuel Tax Credits
Alternative Energy Tax Credits [Line Items]
(Provision) benefit for income taxes				(102,000,000)
Accrued Interest Related to Cellulosic Biofuel Tax Credits
Alternative Energy Tax Credits [Line Items]
(Provision) benefit for income taxes				(1,900,000)
Other Long-Term Liabilities \| Alternative Energy Tax Credits
Alternative Energy Tax Credits [Line Items]
Alternative energy tax credits				13,100,000
Deferred Tax Asset \| Alternative Energy Tax Credits
Alternative Energy Tax Credits [Line Items]
Alternative energy tax credits				$ 49,000,000