Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of other (increase) decrease of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Other Assets (Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended		1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Oct. 31, 2014	Apr. 30, 2014	Dec. 31, 2012
Goodwill [Line Items]
Goodwill	$ 62,016us-gaap_Goodwill	$ 62,016us-gaap_Goodwill			$ 29,990us-gaap_Goodwill
Goodwill, Other Changes	0us-gaap_GoodwillOtherChanges
Goodwill, Acquired During Period		32,026us-gaap_GoodwillAcquiredDuringPeriod
Olefins [Member]
Goodwill [Line Items]
Goodwill	29,990	29,990			29,990
Goodwill, Other Changes	0
Goodwill, Acquired During Period		0
Vinyls [Member]
Goodwill [Line Items]
Goodwill	32,026	32,026			0
Goodwill, Other Changes	0
Goodwill, Acquired During Period		$ 32,026
Minimum [Member]
Goodwill [Line Items]
Discounted cash flow projections period			2015	2014
Maximum [Member]
Goodwill [Line Items]
Discounted cash flow projections period			2023	2023,