v2.4.0.6

Other Assets (Narrative) (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended | 1 Months Ended
--- | --- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 | Oct. 31, 2011 Olefins [Member] years | Oct. 31, 2011 Minimum [Member] | Oct. 31, 2011 Maximum [Member]
Other Assets [Line Items] |  |  |  |  |  |
Amortization expense of other assets | $ 22,812 | $ 25,142 | $ 24,327 |  |  |
Future amortization expense, 2012 | 3,292 |  |  |  |  |
Future amortization expense, 2013 | 3,246 |  |  |  |  |
Future amortization expense, 2014 | 2,707 |  |  |  |  |
Future amortization expense, 2015 | 2,707 |  |  |  |  |
Future amortization expense, 2016 | 2,653 |  |  |  |  |
Discounted cash flow projections period |  |  |  |  | 2012 | 2020
Number of years forecasted to test for impairment of goodwill |  |  |  | 9 |  |
Rate used to discount future cash flows for goodwill impairment test |  |  |  | 8.80% |  |
Percentage future cash flows of segment could decrease by and not be impaired |  |  |  | 20.00% |  |
Unrealized gain on available for sale securities | 1,185 |  |  |  |  |
Tax expenses, unrealized gain on available for sale securities | $ 663 |  |  |  |  |

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- Definition The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 21 -Subparagraph d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563 + Details
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- Definition This item represents the tax effects occurring during the period which are related to the net unrealized gain (loss) resulting from changes in the fair [carrying] value during the period of available-for-sale securities. Such tax affects would have been charged or credited directly to other comprehensive income or to related components of shareholders' equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 11 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6909487&loc=d3e39076-109324 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 21 -Subparagraph d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 36 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 13 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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