Segment Disclosures - Segment Earnings From Operations (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Apr. 01, 2018
Earnings from Operations
Gross profit	$ 251.6	$ 238.2
SG&A expenses	(234.8)	(226.2)
Earnings from operations	16.8	12.0
Gain on investment in Persol Holdings	13.2	23.7
Other expense, net	(1.1)	(1.7)
Earnings before taxes and equity in net earnings (loss) of affiliate	28.9	34.0
Less: Intersegment
Earnings from Operations
Gross profit	(0.6)	(0.7)
SG&A expenses	0.6	0.7
Earnings from operations	0.0	0.0
Corporate
Earnings from Operations
Earnings from operations	(28.2)	(25.1)
Americas Staffing \| Reporting Segments
Earnings from Operations
Gross profit	117.2	108.0
SG&A expenses	(101.2)	(91.9)
Earnings from operations	16.0	16.1
Global Talent Solutions \| Reporting Segments
Earnings from Operations
Gross profit	100.4	91.8
SG&A expenses	(74.7)	(75.8)
Earnings from operations	25.7	16.0
International Staffing \| Reporting Segments
Earnings from Operations
Gross profit	34.6	39.1
SG&A expenses	(31.3)	(34.1)
Earnings from operations	$ 3.3	$ 5.0

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting.

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