Information On Business Segments (Operating Income by Segment) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Operating income	[1]	$ 51.8	$ 43.3	$ 63.5	$ 50.5
Interest expense		9.9	10.8	19.3	20.6
Interest income		(1.4)	(2.0)	(2.4)	(3.3)
Non-operating pension income		(2.3)	(2.1)	(4.5)	(4.2)
Other expense (income), net		1.6	(1.5)	1.0	(0.8)
Income before income tax		44.0	38.1	50.1	38.2
Operating Segment
Segment Reporting Information [Line Items]
Operating income	[1]	63.2	55.1	86.0	74.6
Corporate
Segment Reporting Information [Line Items]
Operating income	[1]	(11.4)	(11.8)	(22.5)	(24.1)
ACCO Brands North America | Operating Segment
Segment Reporting Information [Line Items]
Operating income	[1]	51.5	51.7	54.4	57.5
ACCO Brands EMEA | Operating Segment
Segment Reporting Information [Line Items]
Operating income	[1]	8.4	(0.6)	22.5	3.0
ACCO Brands International | Operating Segment
Segment Reporting Information [Line Items]
Operating income	[1]	$ 3.3	$ 4.0	$ 9.1	$ 14.1

[1] Operating income as presented in the segment table above is defined as i) net sales; ii) less cost of products sold; iii) less selling, general and administrative expenses; iv) less amortization of intangibles; and v) less restructuring charges.