Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 2.6	$ 43.1	$ 58.6	$ 123.5
Other comprehensive income (loss), net of tax:
Translation adjustments and related hedging instruments	59.3	(9.8)	56.6	(4.0)
Cash flow hedges	0.8	(0.4)	(2.4)	(3.3)
Total other comprehensive income (loss)	60.1	(10.2)	54.2	(7.3)
Total comprehensive income	62.7	32.9	112.8	116.2
Comprehensive income attributable to noncontrolling interests	(0.9)	(0.1)	(1.3)	(0.2)
Comprehensive income attributable to Avient common shareholders	$ 61.8	$ 32.8	$ 111.5	$ 116.0