GUARANTOR INFORMATION (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Guarantor Condensed Consolidating Balance Sheet Information
Ownership interest (as a percent)	100.00%
Assets
Cash and cash equivalents	$ 134.7	$ 166.8	$ 86.5	$ 166.5
Receivables, net of allowance for doubtful accounts	478.5	467.0
Inventories	419.1	353.7
Prepaid expenses and other	60.1	89.7
Deferred income taxes	32.5	28.0
Total current assets	1,124.9	1,105.2
Property, plant and equipment, net	1,641.7	1,665.7
Goodwill	1,731.3	1,741.0
Customer relationships, net	1,006.4	1,024.5
Other intangible assets, net	67.0	68.1
Other assets, net	71.4	69.8
Total assets	5,642.7	5,674.3
Liabilities and Equity:
Current portion of long-term debt	2.5	2.8
Accounts payable	316.3	295.5
Interest payable	12.7	15.2
Income taxes payable	5.4	3.1
Accrued compensation	22.4	33.6
Other accrued current liabilities	116.7	133.9
Total current liabilities	476.0	484.1
Long-term debt, excluding the current portion of long-term debt	1,382.0	1,327.8
Lease financing obligation	86.4	94.2
Deferred income taxes	757.1	767.5
Pensions and other post-retirement benefits	245.8	250.5
Other non-current liabilities	150.0	161.2
Total liabilities	3,097.3	3,085.3
Equity:
Total Axiall stockholders' equity	2,434.5	2,481.1
Noncontrolling interest	110.9	107.9
Total equity	2,545.4	2,589.0
Total liabilities and equity	5,642.7	5,674.3
4.875 Notes
Guarantor Condensed Consolidating Balance Sheet Information
Interest rate (as a percent)	4.875%	4.875%
4.625 Notes
Guarantor Condensed Consolidating Balance Sheet Information
Interest rate (as a percent)	4.625%	4.625%
Spinco and the other Guarantor Subsidiaries
Guarantor Condensed Consolidating Balance Sheet Information
Ownership interest (as a percent)	100.00%
Reportable legal entity | Parent Company
Assets
Receivables, net of allowance for doubtful accounts	367.0	162.8
Prepaid expenses and other	0.5	0.1
Deferred income taxes	3.1	3.1
Total current assets	370.6	166.0
Property, plant and equipment, net	11.7	12.0
Long-term receivables - affiliates	900.6	1,292.9
Other assets, net	16.7	17.0
Investments in subsidiaries	1,974.2	1,682.7
Total assets	3,273.8	3,170.6
Liabilities and Equity:
Accounts payable	317.6	97.2
Interest payable	8.6	3.0
Other accrued current liabilities	15.1	14.3
Total current liabilities	341.3	114.5
Long-term debt, excluding the current portion of long-term debt	450.0	450.0
Deferred income taxes	16.2	10.0
Pensions and other post-retirement benefits	4.1	4.4
Other non-current liabilities	27.7	110.6
Total liabilities	839.3	689.5
Equity:
Total Axiall stockholders' equity	2,434.5	2,481.1
Total equity	2,434.5	2,481.1
Total liabilities and equity	3,273.8	3,170.6
Reportable legal entity | Spinco | 4.625 Notes, 4.875 Notes and Term Loan credit agreement
Assets
Other assets, net	11.5	12.4
Investments in subsidiaries	2,839.7	2,831.2
Total assets	2,851.2	2,843.6
Liabilities and Equity:
Current portion of long-term debt		2.8
Accounts payable	393.7	178.6
Interest payable	4.2	12.2
Total current liabilities	397.9	193.6
Long-term debt, excluding the current portion of long-term debt	688.0	877.8
Long-term payables - affiliates	900.0	900.0
Total liabilities	1,985.9	1,971.4
Equity:
Total Axiall stockholders' equity	865.3	872.2
Total equity	865.3	872.2
Total liabilities and equity	2,851.2	2,843.6
Reportable legal entity | Guarantor Subsidiaries Excluding Eagle Spinco Inc. | 4.625 Notes, 4.875 Notes and Term Loan credit agreement
Assets
Cash and cash equivalents	76.3	78.2	48.6	76.9
Receivables, net of allowance for doubtful accounts	745.6	509.7
Inventories	311.6	257.0
Prepaid expenses and other	48.4	83.0
Deferred income taxes	29.4	24.9
Total current assets	1,211.3	952.8
Property, plant and equipment, net	1,367.2	1,367.7
Goodwill	1,493.7	1,493.7
Customer relationships, net	864.2	877.9
Other intangible assets, net	66.7	67.8
Other assets, net	39.0	31.7
Investments in subsidiaries	568.5	290.5
Total assets	5,610.6	5,082.1
Liabilities and Equity:
Current portion of long-term debt	2.5
Accounts payable	268.7	249.8
Income taxes payable	2.2	0.9
Accrued compensation	15.7	25.3
Other accrued current liabilities	71.3	90.3
Total current liabilities	360.4	366.3
Long-term debt, excluding the current portion of long-term debt	244.0
Deferred income taxes	705.2	720.4
Pensions and other post-retirement benefits	231.7	235.7
Other non-current liabilities	121.5	118.7
Total liabilities	1,662.8	1,441.1
Equity:
Total Axiall stockholders' equity	3,947.8	3,641.0
Total equity	3,947.8	3,641.0
Total liabilities and equity	5,610.6	5,082.1
Reportable legal entity | Guarantor Subsidiaries Including Eagle Spinco Inc | 4.625 Notes, 4.875 Notes and Term Loan credit agreement
Assets
Cash and cash equivalents	76.3	78.2	48.6	76.9
Receivables, net of allowance for doubtful accounts	718.8	493.9
Inventories	311.6	257.0
Prepaid expenses and other	48.4	83.0
Deferred income taxes	29.4	24.9
Total current assets	1,184.5	937.0
Property, plant and equipment, net	1,367.2	1,367.7
Goodwill	1,493.7	1,493.7
Customer relationships, net	864.2	877.9
Other intangible assets, net	66.7	67.8
Other assets, net	49.8	44.0
Investments in subsidiaries	568.5	290.5
Total assets	5,594.6	5,078.6
Liabilities and Equity:
Current portion of long-term debt	2.5	2.8
Accounts payable	635.6	412.5
Interest payable	4.1	12.2
Income taxes payable	2.2	0.9
Accrued compensation	15.7	25.3
Other accrued current liabilities	71.3	90.3
Total current liabilities	731.4	544.0
Long-term debt, excluding the current portion of long-term debt	932.0	877.8
Long-term payables - affiliates	900.0	900.0
Deferred income taxes	704.6	720.4
Pensions and other post-retirement benefits	231.7	235.7
Other non-current liabilities	121.5	118.7
Total liabilities	3,621.2	3,396.6
Equity:
Total Axiall stockholders' equity	1,973.4	1,682.0
Total equity	1,973.4	1,682.0
Total liabilities and equity	5,594.6	5,078.6
Reportable legal entity | Non-Guarantor Subsidiaries | 4.625 Notes, 4.875 Notes and Term Loan credit agreement
Assets
Cash and cash equivalents	58.4	88.6	37.9	89.6
Receivables, net of allowance for doubtful accounts	77.2	71.4
Inventories	107.5	96.7
Prepaid expenses and other	11.2	6.6
Total current assets	254.3	263.3
Property, plant and equipment, net	262.8	286.0
Goodwill	237.6	247.3
Customer relationships, net	142.2	146.6
Other intangible assets, net	0.3	0.3
Other assets, net	4.9	9.4
Total assets	902.1	952.9
Liabilities and Equity:
Accounts payable	47.6	46.9
Income taxes payable	3.2	2.2
Accrued compensation	6.7	8.3
Other accrued current liabilities	30.3	29.3
Total current liabilities	87.8	86.7
Long-term payables - affiliates	0.6	392.9
Lease financing obligation	86.4	94.2
Deferred income taxes	36.3	37.7
Pensions and other post-retirement benefits	10.0	10.4
Other non-current liabilities	9.4	9.0
Total liabilities	230.5	630.9
Equity:
Total Axiall stockholders' equity	560.7	214.1
Noncontrolling interest	110.9	107.9
Total equity	671.6	322.0
Total liabilities and equity	902.1	952.9
Eliminations
Assets
Receivables, net of allowance for doubtful accounts	(684.5)	(261.1)
Total current assets	(684.5)	(261.1)
Long-term receivables - affiliates	(900.6)	(1,292.9)
Other assets, net		(0.6)
Investments in subsidiaries	(2,542.7)	(1,973.2)
Total assets	(4,127.8)	(3,527.8)
Liabilities and Equity:
Accounts payable	(684.5)	(261.1)
Total current liabilities	(684.5)	(261.1)
Long-term payables - affiliates	(900.6)	(1,292.9)
Deferred income taxes		(0.6)
Other non-current liabilities	(8.6)	(77.1)
Total liabilities	(1,593.7)	(1,631.7)
Equity:
Total Axiall stockholders' equity	(2,534.1)	(1,896.1)
Total equity	(2,534.1)	(1,896.1)
Total liabilities and equity	$ (4,127.8)	$ (3,527.8)