Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

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The calculated fixed charge coverage ratio for the revolving credit facility.

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Represents the minimum borrowing availability, as a percentage of total bank commitments, that must be maintained under the revolving credit facility in order to make acquisitions or investments.

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The maximum investment amount in specified joint ventures allowed under debt covenants.

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Long-Term Debt (Debt Covenants And Credit Facility) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Debt Instrument [Line Items]
Quarterly dividend, per share	$ 0.1875	$ 4.2725	$ 0.2746	$ 0.2420
Investment in joint ventures		$ 200,000
Suzhou Huasu Plastics Co. Ltd. [Member]
Debt Instrument [Line Items]
Investment in joint ventures		55,000
Debt Covenant [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Maximum percentage of income distribution		50.00%
Maximum distribution percentage of specified net cash proceeds		100.00%
Minimum [Member] \| Debt Covenant [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio for debt covenant		1
Maximum [Member]
Debt Instrument [Line Items]
Maximum unrestricted distributions allowable		100,000
Maximum [Member] \| Debt Covenant [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Maximum Unrestricted Quarterly Dividends Allowable Under Debt Covenants		$ 0.20
25% Of Total Bank Commitments [Member] \| Minimum [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing availability of bank commitments, minimum	100,000	100,000
Percentage of borrowing availability of bank commitments	25.00%	25.00%
17.5% Of Total Bank Commitments [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum distributions allowable		25,000
17.5% Of Total Bank Commitments [Member] \| Minimum [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing availability of bank commitments, minimum	$ 70,000	$ 70,000
Percentage of borrowing availability of bank commitments	17.50%	17.50%