Acquisitions and Dispositions - Additional Information (Details)						1 Months Ended	3 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) Business	Aug. 07, 2019	Jul. 10, 2019	Jul. 09, 2019	Apr. 03, 2019 USD ($)	Dec. 31, 2018 USD ($) business_unit	Sep. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2019
Business Acquisition [Line Items]
Percentage interest acquired												51.00%
Total cash consideration paid for acquisitions, net of cash acquired									$ 2,600,000	$ 47,700,000	$ 51,800,000
Business combination, net of cash acquired									700,000	(77,800,000)	9,100,000
Total contingent consideration payments for acquisitions											42,700,000
Payment for contingent consideration liability, financing activities									1,900,000	13,000,000.0	18,600,000
Goodwill acquired during the period									0	48,000,000.0	6,100,000
Intangible assets acquired during the period									$ 0		$ 700,000
Non-cash gain on deconsolidation										30,400,000
Number of businesses disposed | Business	4
Net proceeds from disposal of businesses	$ 5,800,000
One-time loss on disposition							$ 5,800,000
ManpowerGroup Greater China Limited
Business Acquisition [Line Items]
Percentage of diluted ownership interest, description									36.87% as the underwriters exercised their overallotment option in full
Foreign currency translation adjustment										6,200,000
ManpowerGroup Greater China Limited | APME
Business Acquisition [Line Items]
Percentage of controlling interest				51.00%
ManpowerGroup Greater China Limited | Initial Public Offering
Business Acquisition [Line Items]
Percentage of shares issued in equity			25.00%
Percentage of diluted ownership interest			38.25%
Percentage of diluted ownership interest, if underwriter exercises of overallotment option in full		36.87%
Netherlands Business Unit | Disposed of by Sale
Business Acquisition [Line Items]
Number of business units sold | business_unit						1
After tax net gain						$ 3,800,000
Selling and Administrative Expenses
Business Acquisition [Line Items]
One-time loss on disposition									$ 5,800,000
Selling and Administrative Expenses | ManpowerGroup Greater China Limited
Business Acquisition [Line Items]
Non-cash gain on deconsolidation										30,400,000
Manpower Switzerland
Business Acquisition [Line Items]
Percentage interest acquired					51.00%
Cash consideration for acquisitions					$ 219,500,000
Acquired interests					58,300,000
Cash and cash equivalents					161,200,000
Total cash impact of the acquisition					98,000,000.0
Cash acquired					317,500,000
Reclassification of foreign currency translation adjustments related to previously held equity interest					32,500,000					32,500,000
Manpower Switzerland | Interest and Other Expenses (Income), Net
Business Acquisition [Line Items]
Non-cash gain on disposition of previously held equity interest					$ 80,400,000			$ 80,400,000
Experis AG
Business Acquisition [Line Items]
Percentage interest acquired					20.00%
2019 Acquisitions Excluding Manpower Switzerland
Business Acquisition [Line Items]
Goodwill acquired during the period										14,200,000
Intangible assets acquired during the period										$ 9,000,000.0