EARNINGS (LOSS) PER COMMON SHARE - Computation of Basic and Diluted Net Income (Loss) Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Numerator:
Net income (loss) attributable to Stericycle, Inc.	$ 39,038	$ 64,795	$ (46,815)	$ 187,615
Mandatory convertible preferred stock dividend	8,957	9,726	27,506	29,853
Gain on repurchase of preferred stock	(5,368)	(6,467)	(14,390)	(7,747)
Net Income (Loss) Attributable to Stericycle, Inc. Common Shareholders	$ 35,449	$ 61,536	$ (59,931)	$ 165,509
Denominator:
Denominator for basic earnings (loss) per share - weighted average shares	85,342,955	85,044,303	85,278,783	84,881,452
Effect of diluted securities:
Dilutive effect of stock-based compensation awards (in shares)	278,229	526,226	0	808,073
Mandatory convertible preferred stock (in shares)	0	0	0	0
Denominator for diluted earnings (loss) per share - adjusted weighted average shares and after assumed exercises (in shares)	85,621,184	85,570,529	85,278,783	85,689,525
Earnings (loss) per share – Basic (in dollars per share)	$ 0.42	$ 0.72	$ (0.70)	$ 1.95
Earnings (loss) per share – Diluted (in dollars per share)	$ 0.41	$ 0.72	$ (0.70)	$ 1.93