Earnings Per Share - Computation of Basic and Diluted Income Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended																12 Months Ended
	Dec. 31, 2016	[1]	Sep. 30, 2016	[2]	Jun. 30, 2016	[3]	Mar. 31, 2016	[4]	Dec. 31, 2015	[5]	Sep. 30, 2015	[6]	Jun. 30, 2015	[7]	Mar. 31, 2015	[8]	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator:
Net income attributable to Packaging Corporation of America	$ 110.6		$ 119.4		$ 115.9		$ 103.7		$ 104.3		$ 127.8		$ 114.0		$ 90.8		$ 449.6	$ 436.8	$ 392.6
Less: distributed and undistributed earnings allocated to participating securities																	(4.4)	(5.2)	(5.7)
Net income attributable to common shareholders																	$ 445.2	$ 431.6	$ 386.9
Denominator:
Weighted average basic common shares outstanding																	93.5	96.6	97.0
Effect of dilutive securities																	0.2	0.1	0.1
Diluted common shares outstanding																	93.7	96.7	97.1
Basic income per common share (US$ per share)	$ 1.17		$ 1.27		$ 1.23		$ 1.09		$ 1.07		$ 1.31		$ 1.16		$ 0.92		$ 4.76	$ 4.47	$ 3.99
Diluted income per common share (US$ per share)	$ 1.17		$ 1.26		$ 1.23		$ 1.09		$ 1.07		$ 1.31		$ 1.16		$ 0.92		$ 4.75	$ 4.47	$ 3.99

[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.