Consolidated Statements of Earnings (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018
Revenue from services	$ 1,367.5	$ 1,386.9	$ 2,750.1	$ 2,756.8
Cost of services	1,123.5	1,146.4	2,254.5	2,278.1
Gross profit	244.0	240.5	495.6	478.7
Selling, general and administrative expenses	221.5	220.1	456.3	446.3
Gain on sale of assets	12.3	0.0	12.3	0.0
Earnings from operations	34.8	20.4	51.6	32.4
Gain (loss) on investment in Persol Holdings	61.2	(52.5)	74.4	(28.8)
Other income (expense), net	0.2	0.6	(0.9)	(1.1)
Earnings (loss) before taxes and equity in net earnings (loss) of affiliate	96.2	(31.5)	125.1	2.5
Income tax expense (benefit)	12.7	(15.6)	19.1	(9.2)
Net earnings (loss) before equity in net earnings (loss) of affiliate	83.5	(15.9)	106.0	11.7
Equity in net earnings (loss) of affiliate	0.3	0.5	(0.1)	2.0
Net earnings (loss)	$ 83.8	$ (15.4)	$ 105.9	$ 13.7
Basic earnings (loss) per share (in dollars per share)	$ 2.12	$ (0.40)	$ 2.69	$ 0.35
Diluted earnings (loss) per share (in dollars per share)	$ 2.12	$ (0.40)	$ 2.68	$ 0.35
Average shares outstanding (millions):
Basic (in shares)	39.1	38.8	39.0	38.7
Diluted (in shares)	39.2	38.8	39.2	38.8
Service
Revenue from services	$ 1,367.5	$ 1,386.9	$ 2,750.1	$ 2,756.8

Amount of income (loss) from continuing operations before addition of income (loss) from equity method investments.

No definition available.

Name:	kelya_IncomeLossfromContinuingOperationsBeforeEquityMethodInvestments
Namespace Prefix:	kelya_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.