Acquisitions (Assets Acquired and Liabilities Assumed - Vinnolit) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended		0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Jul. 31, 2014	Dec. 31, 2012
Business Acquisition [Line Items]
Total purchase consideration	$ 736,224	$ 178,309
Goodwill	62,016	62,016		29,990
Vinnolit [Member]
Business Acquisition [Line Items]
Cash paid to Sellers			309,619
Cash deposited in escrow			13,390
Retirement of long-term debt as of July 31, 2014, on behalf of the Sellers			413,215
Total purchase consideration			736,224
Cash			125,137
Working capital, excluding inventory and cash			15,373
Inventories			114,961
Property, plant and equipment			469,484
Investments			51,552
Other assets			76,828
Deferred income tax asset - current			7,909
Deferred income tax asset - non-current			27,387
Pension obligation			117,970
Other long-term liabilities			(10,723)
Power purchase agreement liability			(10,826)
Deferred income tax liability - current			(6,845)
Deferred income tax liability - non-current			(79,235)
Total identifiable net assets			736,224
Goodwill			0
Consideration transferred			736,224
Fair value of accounts receivable			181,890
Gross contractual amount of accounts receivable			183,833
Uncollectable accounts receivable			1,943
Adjustment to inventory fair value			16,900
Weighted-average life of forward purchase contracts			3 years
Trademarks and Trade Names [Member] | Vinnolit [Member]
Business Acquisition [Line Items]
Intangible assets			40,170
Developed Technology Rights [Member] | Vinnolit [Member]
Business Acquisition [Line Items]
Intangible assets			31,600
Other [Member] | Vinnolit [Member]
Business Acquisition [Line Items]
Intangible assets			$ 1,422