Segment Information (Schedule Of Segment Information) (Details) (USD $) In Millions, 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, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Intersegment sales																	$ 0	$ 0	$ 0
Total Sales																	3,835.5	3,771.2	2,860.8
Operating 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
Depreciation and amortization																	123.9	109.8	69.8
Capital Expenditures (1a)																	92.8	76.4	57.4
Total Assets	2,711.2								2,944.1								2,711.2	2,944.1	2,128.0
Global Specialty Engineered Materials
Segment Reporting Information [Line Items]
Revenue, Net																	555.2	571.9	504.9
Intersegment sales																	43.1	43.6	38.7
Total Sales																	598.3	615.5	543.6
Operating Income																	72.4	57.2	47.0
Depreciation and amortization																	16.7	18.8	14.3
Capital Expenditures (1a)																	15.2	14.3	12.9
Total Assets	370.5								379.6								370.5	379.6	396.6
Global Color, Additives and Inks
Segment Reporting Information [Line Items]
Revenue, Net																	835.0	844.6	776.1
Intersegment sales																	15.8	7.7	2.1
Total Sales																	850.8	852.3	778.2
Operating Income																	124.9	104.0	75.3
Depreciation and amortization																	41.4	38.8	32.9
Capital Expenditures (1a)																	28.1	29.3	28.2
Total Assets	937.7								962.0								937.7	962.0	901.7
Designed Structures and Solutions [Member]
Segment Reporting Information [Line Items]
Revenue, Net																	616.5	597.3
Intersegment sales																	1.0	0.1
Total Sales																	617.5	597.4
Operating Income																	45.1	33.4
Depreciation and amortization																	24.4	21.2
Capital Expenditures (1a)																	25.6	13.4
Total Assets	490.2								549.4								490.2	549.4
Performance Products and Solutions
Segment Reporting Information [Line Items]
Revenue, Net																	728.2	690.9	554.9
Intersegment sales																	88.4	82.3	75.4
Total Sales																	816.6	773.2	630.3
Operating Income																	63.1	56.0	38.8
Depreciation and amortization																	17.7	15.5	13.7
Capital Expenditures (1a)																	15.2	12.4	4.6
Total Assets	265.5								278.7								265.5	278.7	205.4
PolyOne Distribution
Segment Reporting Information [Line Items]
Revenue, Net																	1,100.6	1,066.5	1,024.9
Intersegment sales																	13.8	8.7	5.4
Total Sales																	1,114.4	1,075.2	1,030.3
Operating Income																	68.2	63.3	66.0
Depreciation and amortization																	0.6	0.6	0.7
Capital Expenditures (1a)																	0.1	0.3	0.6
Total Assets	214.2								216.7								214.2	216.7	212.9
Corporate and eliminations
Segment Reporting Information [Line Items]
Revenue, Net																	0	0	0
Intersegment sales																	(162.1)	(142.4)	(121.6)
Total Sales																	(162.1)	(142.4)	(121.6)
Operating Income																	(218.6)	(82.4)	(89.6)
Depreciation and amortization																	23.1	13.9	4.2
Capital Expenditures (1a)																	8.6	6.5	8.5
Total Assets	433.1								557.7								433.1	557.7	411.4
Resin Business [Member]
Segment Reporting Information [Line Items]
Capital Expenditures (1a)																		0.2	2.6
Depreciation and Amortization, Discontinued Operations																		1.0	4.0
Continuing Operations [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization																	123.9	108.8	65.8
Capital Expenditures (1a)																	$ 92.8	$ 76.2	$ 54.8

[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.