Selected Quarterly Financial Data (Schedule Of Quarterly Financial Data) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended																	12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Selected Quarterly Financial Data [Line Items]
Sales	$ 869.3	[1]	$ 958.4	[2]	$ 1,005.5	[3]	$ 1,002.3	[4]	$ 923.6	[5]	$ 1,008.9	[6]	$ 1,037.6	[7]	$ 801.1	[8]		$ 3,835.5	$ 3,771.2	$ 2,860.8
Gross Margin	152.6	[1]	182.6	[2]	184.5	[3]	188.2	[4]	114.9	[5]	181.3	[6]	203.7	[7]	162.3	[8]		707.9	662.2	531.1
Operating (loss)/income	(14.3)	[1]	63.6	[2]	49.4	[3]	56.4	[4]	48.7	[5]	61.6	[6]	80.7	[7]	40.5	[8]		155.1	231.5	137.5
Net (loss)/income from continuing operations	(15.0)	[1]	32.3	[2]	30.7	[3]	29.2	[4]	20.6	[5]	23.0	[6]	38.3	[7]	11.0	[8]
Net (loss)/income from continuing operations attributable to PolyOne shareholders	(14.6)	[1]	32.3	[2]	30.9	[3]	29.4	[4]	21.0	[5]	23.2	[6]	38.6	[7]	11.2	[8]
Basic net income - continuing operations	$ (0.16)	[1]	$ 0.35	[2]	$ 0.33	[3]	$ 0.31	[4]	$ 0.22	[5]	$ 0.24	[6]	$ 0.39	[7]	$ 0.12	[8]		$ 0.85	$ 0.98	$ 0.60
Diluted net income - continuing operations	$ (0.16)	[1]	$ 0.35	[2]	$ 0.33	[3]	$ 0.31	[4]	$ 0.22	[5]	$ 0.24	[6]	$ 0.39	[7]	$ 0.12	[8]		$ 0.83	$ 0.97	$ 0.59
Mark-to-market actuarial net losses (gains)	56.5								(44.0)								42.0
Environmental remediation expense	2.6		5.9						52.6		5.3		1.3		2.0
Reimbursement of previously incurred environmental cost	2.1		1.6						3.4				14.9		5.2
Acquisition related costs											1.2		4.9		8.7
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax																		0	223.7	0
Restructuring charges																		94.1	52.0
Tax benefit associated with our investments in certain foreign affiliates					5.4													(13.4)	0	0
Mark-to-market actuarial net losses (gains)											7.0
Payments of Debt Extinguishment Costs											5.2				10.6
SunBelt
Selected Quarterly Financial Data [Line Items]
Pre-tax gain associated with estimated earnout of SunBelt									26.8
Plant Closure and Reductions in Force
Selected Quarterly Financial Data [Line Items]
Restructuring charges	23.2		17.9		35.1		17.9		28.3		10.9		2.9		9.9
325211 Plastics Material and Resin Manufacturing [Member]
Selected Quarterly Financial Data [Line Items]
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax													$ 223.7

[1] Included for the fourth quarter 2014 are: 1) mark-to-market pension and other post-retirement charge of $56.5 million, 2) employee separation and restructuring costs of $23.2 million, 3) environmental remediation costs of $2.6 million and 5) a gain related to the reimbursement of previously incurred environmental costs of $2.1 million.

[2] Included for the third quarter 2014 are: 1) $17.9 million in employee separation and restructuring costs, 2) $5.9 million in environmental remediation costs and 3) a gain related to the reimbursement of previously incurred environmental costs of $1.6 million.

[3] Included for the second quarter 2014 are: 1) $35.1 million in employee separation and restructuring costs and 2) $5.4 million tax benefit associated with our investments in certain foreign affiliates.

[4] Included for the first quarter 2014 are: 1) $17.9 million in employee separation and restructuring costs.

[5] Included for the fourth quarter 2013 are: 1) gains from the SunBelt earn-out of $26.8 million, 2) mark-to-market pension and other post-retirement benefit gains of $44.0 million, 3) environmental remediation costs of $52.6 million, 4) a gain related to the reimbursement of previously incurred environmental costs of $3.4 million and 5) employee separation and restructuring costs of $28.3 million.

[6] Included for the third quarter 2013 are: 1) $5.3 million in environmental remediation costs, 2) $10.9 million in employee separation and restructuring costs, 3) $7.0 million gain on commercial litigation, 4) $5.2 million in debt extinguishment costs associated with our outstanding debt repurchases and 5) $1.2 million of acquisition and divestiture-related costs.

[7] Included for the second quarter 2013 are: 1) pre-tax gain of $223.7 million related to the sale of the Resin Business, 2) $2.9 million in employee separation and restructuring costs, 3) acquisition and divestiture-related costs of $4.9 million, 4) environmental remediation costs of $1.3 million and 5) a gain related to the reimbursement of previously incurred environmental costs of $14.9 million.

[8] Included for the first quarter 2013 are: 1) $9.9 million in employee separation and restructuring costs 2) acquisition and divestiture-related costs of $8.7 million, 3) environmental remediation costs of $2.0 million, 4) a gain related to the reimbursement of previously incurred environmental costs of $5.2 million and 5) $10.6 million in debt extinguishment costs related to the early retirement of our senior secured term loan.