Goodwill and Identifiable Intangibles (Goodwill) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015
Goodwill [Roll Forward]
Beginning Balance		$ 544.9	$ 568.3
Translation		(48.0)	(23.4)
Ending Balance		496.9	544.9
Goodwill, Impaired, Accumulated Impairment Loss
Goodwill				$ 712.0
Accumulated impairment losses				(215.1)
Goodwill		544.9	568.3	496.9
Goodwill, Impairment Loss	$ 0.0
ACCO Brands North America
Goodwill [Roll Forward]
Beginning Balance		387.6	393.1
Translation		(10.1)	(5.5)
Ending Balance		377.5	387.6
Goodwill, Impaired, Accumulated Impairment Loss
Goodwill				508.4
Accumulated impairment losses				(130.9)
Goodwill		387.6	393.1	377.5
ACCO Brands International
Goodwill [Roll Forward]
Beginning Balance		150.5	168.4
Translation		(37.9)	(17.9)
Ending Balance		112.6	150.5
Goodwill, Impaired, Accumulated Impairment Loss
Goodwill				196.8
Accumulated impairment losses				(84.2)
Goodwill		150.5	168.4	112.6
Computer Products Group
Goodwill [Roll Forward]
Beginning Balance		6.8	6.8
Translation		0.0	0.0
Ending Balance		6.8	6.8
Goodwill, Impaired, Accumulated Impairment Loss
Goodwill				6.8
Accumulated impairment losses				0.0
Goodwill		$ 6.8	$ 6.8	$ 6.8