Condensed Consolidated Statements of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Sales	$ 609.1	$ 748.2	$ 1,320.6	$ 1,498.8
Cost of sales	459.4	572.9	999.4	1,155.4
Gross margin	149.7	175.3	321.2	343.4
Selling and administrative expense	111.7	129.2	230.4	250.2
Operating income	38.0	46.1	90.8	93.2
Interest expense, net	(16.2)	(16.2)	(25.6)	(32.1)
Other income, net	9.5	0.7	11.1	0.8
Income from continuing operations before income taxes	31.3	30.6	76.3	61.9
Income tax expense	(7.9)	(7.4)	(19.8)	(16.2)
Net income from continuing operations	23.4	23.2	56.5	45.7
(Loss) income from discontinued operations, net of income taxes	(0.2)	18.9	(0.5)	34.7
Net income	23.2	42.1	56.0	80.4
Net income attributable to noncontrolling interests	(0.4)	0.0	(0.4)	(0.1)
Net income attributable to Avient common shareholders	$ 22.8	$ 42.1	$ 55.6	$ 80.3
Earnings per share attributable to Avient common shareholders - Basic:
Continuing operations (in USD per share)	$ 0.25	$ 0.30	$ 0.63	$ 0.59
Discontinued operations (in USD per share)	0	0.24	0	0.45
Total (in USD per share)	0.25	0.54	0.63	1.04
Earnings (loss) per share attributable to Avient common shareholders - Diluted:
Continuing operations (in USD per share)	0.25	0.30	0.63	0.58
Discontinued operations (in USD per share)	0	0.24	(0.01)	0.45
Total (in USD per share)	$ 0.25	$ 0.54	$ 0.62	$ 1.03
Weighted-average shares used to compute earnings per common share:
Basic (in shares)	91.4	77.3	88.8	77.5
Plus dilutive impact of share-based compensation (in shares)	0.4	0.4	0.6	0.5
Diluted (in shares)	91.8	77.7	89.4	78.0
Anti-dilutive shares not included in diluted common shares outstanding (in shares)	1.2	0.8	0.8	0.9
Cash dividends declared per share of common stock (in USD per share)	$ 0.2025	$ 0.1950	$ 0.4050	$ 0.3900