Acquisitions (Narrative) (Details) € in Millions, $ in Millions			3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 31, 2017 USD ($)	Jan. 31, 2017 EUR (€)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)	Jan. 31, 2017 EUR (€)	Jan. 27, 2017 USD ($)	Jan. 27, 2017 EUR (€)
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired					$ 292.3	$ 88.8
Net sales			$ 532.2	$ 431.3	1,382.0	1,119.5
Esselte Group Holdings AB
Business Acquisition [Line Items]
Goodwill	$ 109.5
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment			5.6
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles			3.0
Payments to Acquire Businesses, Gross	326.8	€ 302.9
Working Capital Adjustments to Purchase Price	0.3
Cash acquired	34.2
Payments to Acquire Businesses, Net of Cash Acquired	292.3
Business Acquisition, Consideration Held in Escrow	8.7	€ 8.1
Net sales			107.7		274.5
Warranty and indemnity insurance policy	$ 43.2							€ 40.0
Selling, General and Administrative Expenses [Member] | Esselte Group Holdings AB
Business Acquisition [Line Items]
Transaction Related Costs			$ 1.6	$ 4.3	$ 5.0	$ 6.3	$ 9.2
Senior Secured Notes | Euro Term Loan A
Business Acquisition [Line Items]
Maximum borrowing capacity									$ 320.8	€ 300.0
Maximum | Esselte Group Holdings AB
Business Acquisition [Line Items]
Escrow period	2 years	2 years
Period of Warranty and Indemnity Policy	7 years	7 years