Investment in PersolKelly Asia Pacific (Details) - USD ($) $ in Millions	Jul. 01, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Investment in equity affiliate	$ 122.0	$ 117.4
Accounts payable and accrued liabilities	$ 505.5	537.7
PersolKelly Asia Pacific [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	49.00%
Due to PersolKelly Asia Pacific	$ 1.0	2.3
PersolKelly Asia Pacific [Member]
Schedule of Equity Method Investments [Line Items]
Accounts payable and accrued liabilities	$ 1.7	$ 2.5

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