Other Income (Expense), Net (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Income and Expenses [Abstract]
Facilities closure costs and other	[1]	$ (1.6)	$ 0.0	$ (5.0)	$ 0.0
Acquisition-related costs	[2]	(2.0)	0.0	(2.3)	0.0
Multiemployer pension withdrawal	[3]	0.0	0.0	(0.9)	0.0
Asset disposals and write-offs		(0.6)	(5.0)	(3.5)	(9.7)
Integration-related and other costs	[4]	0.0	(2.4)	0.0	(9.0)
Sale of St. Helens paper mill site	[5]	0.0	6.7	0.0	6.7
DeRidder restructuring	[6]	0.0	3.8	0.0	3.6
Refundable state tax credit	[7]	0.0	0.0	0.0	3.6
Other		(2.0)	0.7	(3.5)	1.9
Other income (expense), net		$ (6.2)	$ 3.8	$ (15.2)	$ (2.9)

[1] The three and nine months ended September 30, 2016 include facilities closure costs related to corrugated products facilities and a paper products facility.

[2] The three and nine months ended September 30, 2016 include acquisition-related costs for the TimBar Corporation acquisition.

[3] The nine months ended September 30, 2016 include costs related to our withdrawal from a multiemployer pension plan for one of our corrugated products facilities.

[4] The three and nine months ended September 30, 2015 include Boise acquisition integration-related and other costs. These costs primarily relate to professional fees, severance, retention, relocation, travel, and other integration-related costs.

[5] The three and nine months ended September 30, 2015 include a gain on the sale of the paper mill site in St. Helens, Oregon, where we ceased paper production in December 2012.

[6] The three and nine months ended September 30, 2015 include amounts from restructuring activities at our mill in DeRidder, Louisiana.

[7] The nine months ended September 30, 2015 include a tax credit from the State of Louisiana related to our capital investment and the jobs retained at the DeRidder, Louisiana mill.