Quarterly Data (Unaudited) (Parenthetical) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended					12 Months Ended
	Apr. 03, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Line Items]
Restructuring costs				$ 39.8	$ 15.3	$ 24.0
Restructuring costs, net of tax				$ 31.4	$ 11.8	$ 18.1
Restructuring costs per diluted share (in dollars per share)				$ (0.51)	$ (0.18)	$ (0.27)
Gain on disposition of previously held controlling interest							$ 30.4
Goodwill and related tax and other charges per diluted share (in dollars per share)			$ (1.26)
Selling and Administrative Expenses
Quarterly Financial Information Disclosure [Line Items]
Goodwill impairment and related charges			$ 65.6
Provision for Income Taxes
Quarterly Financial Information Disclosure [Line Items]
Goodwill impairment, related tax charges			$ 10.3
Manpower Switzerland
Quarterly Financial Information Disclosure [Line Items]
Gain on disposition of previously held equity interest per diluted share (in dollars per share)			$ 1.32
Manpower Switzerland | Interest and Other Expenses (Income), Net
Quarterly Financial Information Disclosure [Line Items]
Gain on disposition of previously held equity interest	$ 80.4		$ 80.4				80.4	$ 80.4	$ 80.4
ManpowerGroup Greater China Limited
Quarterly Financial Information Disclosure [Line Items]
Gain on disposition of previously held controlling interest		$ 30.4
Gain on disposition of previously held controlling interest per diluted share (in dollars per share)		$ 0.50
ManpowerGroup Greater China Limited | Selling and Administrative Expenses
Quarterly Financial Information Disclosure [Line Items]
Gain on disposition of previously held controlling interest							$ 30.4