CONDENSED CONSOLIDATED STATEMENTS OF INCOME (LOSS) (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Statement [Abstract]
Revenues	$ 679.8	$ 672.7	$ 1,344.0	$ 1,340.7
Cost of revenues	419.3	403.6	839.0	810.2
Gross profit	260.5	269.1	505.0	530.5
Selling, general and administrative expenses	222.4	213.5	461.0	415.8
Income from operations	38.1	55.6	44.0	114.7
Interest expense, net	(18.5)	(17.9)	(34.8)	(36.3)
Other (expense) income, net	(0.7)	0.7	(1.5)	0.0
Income before income taxes	18.9	38.4	7.7	78.4
Income tax expense	(8.4)	(9.1)	(11.3)	(22.9)
Net income (loss)	10.5	29.3	(3.6)	55.5
Net income attributable to noncontrolling interests	0.0	0.0	(0.2)	(0.1)
Net income (loss) attributable to Stericycle, Inc. common shareholders	$ 10.5	$ 29.3	$ (3.8)	$ 55.4
Earnings (loss) per common share attributable to Stericycle, Inc. common shareholders
Basic (in dollars per share)	$ 0.11	$ 0.32	$ (0.04)	$ 0.60
Diluted (in dollars per share)	$ 0.11	$ 0.32	$ (0.04)	$ 0.60
Weighted average number of common shares outstanding:
Basic (in shares)	92.1	91.8	92.0	91.7
Diluted (in shares)	92.2	92.1	92.0	92.1