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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Business Combination, Annual Production Capacity

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Acquisitions (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended	5 Months Ended	0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 31, 2014	Dec. 31, 2014	May 01, 2013 lb
Business Acquisition [Line Items]
Total purchase consideration	$ 736,224	$ 178,309
Cash paid for purchase	611,087	178,309	0
Vinnolit [Member]
Business Acquisition [Line Items]
Total purchase consideration				736,224
Net sales contributed by acquired business since acquisition date					431,407
Net loss contributed by acquired business since acquisition date					(3,718)
Transaction related costs	13,427
Pipe and Foundation Group [Member]
Business Acquisition [Line Items]
Combined annual capacity						150,000,000
Cash paid for purchase						178,309
Transaction related costs		$ 1,124
PVC Resin Member [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Combined annual capacity				1,700,000,000
Vinyl Chloride Monomer [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Combined annual capacity				1,500,000,000
Caustic Soda [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Combined annual capacity				1,000,000,000