Restructuring (Restructuring Charges and Reconciliation) (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
		Dec. 31, 2017	Dec. 31, 2018		Dec. 31, 2017	Dec. 31, 2016
Restructuring Reserve [Roll Forward]
Balance at beginning of period			$ 13.3		$ 1.5	$ 1.0
Provision			11.7		21.7	5.4
Cash expenditures			(14.7)		(13.4)	(4.9)
Non-cash Items/ Currency Change			(0.6)		0.7
Balance at end of period		$ 13.3	9.7		13.3	1.5
Proceeds from Sale of Property, Plant, and Equipment			0.2		4.2	0.7
Employee termination costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period			12.0		1.4	0.9
Provision			8.3		18.2	5.2
Cash expenditures			(12.1)		(9.6)	(4.7)
Non-cash Items/ Currency Change			0.3		0.5
Balance at end of period		12.0	$ 7.9	[1]	12.0	1.4
Period over which restructuring and related costs are to be paid			12 months
Termination of lease agreements
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost Remaining			$ 0.4
Restructuring Reserve [Roll Forward]
Balance at beginning of period			0.8		0.1	0.1
Provision			3.2		2.4	0.2
Cash expenditures			(2.0)		(3.1)	(0.2)
Non-cash Items/ Currency Change			0.2		0.2
Balance at end of period		0.8	$ 1.8	[2]	0.8	0.1
Period over which restructuring and related costs are to be paid			3 months
Other
Restructuring Reserve [Roll Forward]
Balance at beginning of period			$ 0.5		0.0
Provision			0.2		1.1
Cash expenditures			(0.6)		(0.7)
Non-cash Items/ Currency Change			0.1		0.0
Balance at end of period		0.5	$ 0.0		0.5	$ 0.0
Esselte Acquisition
Restructuring Reserve [Roll Forward]
Restructuring Liabilities Assumed in Business Combination	[3]				2.8
Esselte Acquisition | Employee termination costs
Restructuring Reserve [Roll Forward]
Restructuring Liabilities Assumed in Business Combination	[3]				1.5
Esselte Acquisition | Termination of lease agreements
Restructuring Reserve [Roll Forward]
Restructuring Liabilities Assumed in Business Combination	[3]				1.2
Esselte Acquisition | Other
Restructuring Reserve [Roll Forward]
Restructuring Liabilities Assumed in Business Combination	[3]				$ 0.1
Buildings
Restructuring Reserve [Roll Forward]
Proceeds from Sale of Property, Plant, and Equipment		3.9
Gain (Loss) on Disposition of Assets		$ 1.5

[1] (1) We expect the remaining $7.9 million employee termination costs to be substantially paid within the next twelve months.

[2] (2) We expect the remaining $1.8 million termination of lease costs to be substantially paid within the next three months.

[3] (3) Restructuring liabilities assumed in the Esselte Acquisition.