XML 34 R44.htm IDEA: XBRL DOCUMENT v2.4.1.9
Goodwill and Intangible Assets Goodwill (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Goodwill [Line Items]    
Goodwill $ 546.6us-gaap_Goodwill $ 546.8us-gaap_Goodwill
Packaging    
Goodwill [Line Items]    
Goodwill 491.4us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= pkg_PackagingMember
491.6us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= pkg_PackagingMember
Paper    
Goodwill [Line Items]    
Goodwill $ 55.2us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= pkg_PaperMember
$ 55.2us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= pkg_PaperMember