Other Expense, Net (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Other Income and Expenses [Abstract]
Facilities closure costs and other	[1]	$ (1.4)	$ 0.0	$ (3.3)	$ 0.0
Acquisition-related costs	[2]	(0.3)	0.0	(0.3)	0.0
Multiemployer pension withdrawal	[3]	(0.9)	0.0	(0.9)	0.0
Asset disposals and write-offs		(1.1)	(3.7)	(2.9)	(4.7)
Integration-related and other costs	[4]	0.0	(3.6)	0.0	(6.7)
DeRidder restructuring	[5]	0.0	1.0	0.0	(0.2)
Refundable state tax credit	[6]	0.0	0.0	0.0	3.6
Other		(1.4)	2.1	(1.6)	1.2
Operating Costs and Expenses		$ 5.1	$ 4.2	$ 9.0	$ 6.8

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

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

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

[4] The three and six months ended June 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 six months ended June 30, 2015 include amounts from restructuring activities at our mill in DeRidder, Louisiana.

[6] The six months ended June 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.