Acquisitions and Dispositions (Narrative) (Details)					3 Months Ended																12 Months Ended
	Nov. 30, 2016 USD ($)	Aug. 29, 2016 USD ($) facility	Apr. 01, 2015 USD ($)	Apr. 28, 2014 USD ($)	Dec. 31, 2016 USD ($)		Sep. 30, 2016 USD ($)	[2]	Jun. 30, 2016 USD ($)	[3]	Mar. 31, 2016 USD ($)	[4]	Dec. 31, 2015 USD ($)		Sep. 30, 2015 USD ($)	[6]	Jun. 30, 2015 USD ($)	[7]	Mar. 31, 2015 USD ($)	[8]	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Business Acquisition [Line Items]
Net sales					$ 1,476,600,000	[1]	$ 1,484,000,000		$ 1,417,400,000		$ 1,401,000,000		$ 1,390,900,000	[5]	$ 1,470,800,000		$ 1,454,300,000		$ 1,425,700,000		$ 5,779,000,000	$ 5,741,700,000	$ 5,852,600,000
Goodwill					737,900,000								544,000,000								737,900,000	544,000,000		$ 546,800,000
TimBar Corporation
Business Acquisition [Line Items]
Number of production facilities acquired | facility		6
Cash paid		$ 386,000,000
Debt, face amount		$ 385,000,000
Debt, term		5 years
Net sales																					$ 116,900,000
Percentage of net sales																					2.00%
Useful life of acquired intangibles		14 years 2 months 18 days
Goodwill		$ 148,100			157,300																$ 157,300
Intangible assets		101,600			94,400																94,400
Property, plant and equipment		96,900			95,300																95,300
Other net assets		$ 39,000			38,600																38,600
TimBar Corporation | Minimum
Business Acquisition [Line Items]
Estimated useful life of asset (in years)		2 years
TimBar Corporation | Maximum
Business Acquisition [Line Items]
Estimated useful life of asset (in years)		24 years
Columbus Container Inc
Business Acquisition [Line Items]
Cash paid	$ 99,700,000
Useful life of acquired intangibles	14 years 4 months 24 days
Goodwill	$ 36,600,000
Intangible assets	26,300,000
Property, plant and equipment	27,200,000
Other net assets	$ 9,600,000
Columbus Container Inc | Minimum
Business Acquisition [Line Items]
Estimated useful life of asset (in years)	1 year
Columbus Container Inc | Maximum
Business Acquisition [Line Items]
Estimated useful life of asset (in years)	32 years
Wholesale Distributor
Business Acquisition [Line Items]
Outstanding stock and voting equity interests acquired		51.00%
Packaging
Business Acquisition [Line Items]
Goodwill					$ 682,700,000								$ 488,800,000								$ 682,700,000	$ 488,800,000		$ 491,600,000
Packaging | Crockett Packaging
Business Acquisition [Line Items]
Business acquisition, cost of acquired entity				$ 21,200,000
Working capital adjustments				$ 700,000
Hexacomb Europe and Mexico | Packaging
Business Acquisition [Line Items]
Proceeds from sale of business net of cash divested			$ 23,000,000

[1] Includes $4.5 million of closure costs related to a corrugated products facility and a paper products facility ($2.9 million after-tax or $0.03 per diluted share), $2.7 million of costs related to ceased production of softwood market pulp operations at our Wallula, Washington mill and the permanent shutdown of the No.1 machine ($1.8 million after-tax or $0.02 per diluted share), and $1.2 million of acquisition-related costs for TimBar Corporation and Columbus Container, Inc. acquisitions ($0.8 million after-tax or $0.01 per diluted share).

[2] Includes $2.0 million of closure costs related to a corrugated products facility and a paper products facility ($1.4 million after-tax or $0.02 per diluted share) and $2.9 million of acquisition-related costs for TimBar Corporation and Columbus Container, Inc. acquisitions ($1.9 million after-tax or $0.02 per diluted share).

[3] Includes $1.7 million of closure costs related to a corrugated products facility and a paper products facility ($1.0 million after-tax or $0.01 per diluted share), $0.3 million of acquisition-related costs for TimBar Corporation ($0.2 million after-tax or $0.0 per diluted share), and $0.9 million related to our withdrawal from a multiemployer pension plan for one of our corrugated products facilities ($0.6 million after-tax or $0.01 per diluted share).

[4] Includes $2.8 million of closure costs related to a corrugated products facility and a paper products facility. ($1.9 million after-tax or $0.02 per diluted share).

[5] Includes $3.5 million of income from DeRidder restructuring ($2.2 million after-tax or $0.02 per diluted share) and $3.8 million of integration-related and other costs ($2.6 million after-tax or $0.03 per diluted share).

[6] Includes $3.8 million of income from DeRidder restructuring ($2.3 million after-tax or $0.02 per diluted share) and $2.4 million of integration-related and other costs ($1.7 million after-tax or $0.02 per diluted share). Also includes $6.7 million gain from the sale of our paper mill site at St. Helens, Oregon ($4.4 million after tax or $0.05 per diluted share).

[7] Includes $1.0 million of income from DeRidder restructuring ($0.7 million after-tax or $0.01 per diluted share) and $3.7 million of integration-related and other costs ($2.3 million after-tax or $0.03 per diluted share).

[8] Includes $10.3 million of DeRidder restructuring charges ($6.6 million after-tax or $0.07 per diluted share) and $3.5 million of integration-related and other costs ($2.2 million after-tax or $0.02 per diluted share). Also includes a $3.6 million tax credit from the State of Louisiana related to our capital investment and the jobs retained at the DeRidder, Louisiana mill.