Accumulated Other Comprehensive Income (Loss) (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Accumulated Other Comprehensive Income (Loss) [Abstract]
Derivative Instruments, beginning balance	$ (4,729)	$ 2,921	$ 1,186	$ (45,249)
Derivative Instruments, before tax	(11,951)	2,711	72,553
Derivative Instruments, tax effect	4,301	(976)	(26,118)
Derivative Instruments, ending balance	(4,729)	2,921	1,186	(45,249)
Pension, Postretirement and Other Post-Employment Benefits, beginning balance	(4,676)	(10,679)	(20,539)	(33,433)
Pension, Postretirement and Other Post-Employment Benefits, before tax	9,345	15,406	20,124
Pension, Postretirement and Other Post-Employment Benefits, tax effect	(3,342)	(5,546)	(7,230)
Pension, Postretirement and Other Post-Employment Benefits, ending balance	(4,676)	(10,679)	(20,539)	(33,433)
Available-for-Sale Securities, beginning balance	1,455	1,341	(500)	(414)
Available-for-Sale Securities, before tax	176	2,877	(136)
Available-for-Sale Securities, tax effect	(62)	(1,036)	50
Available-for-Sale Securities, ending balance	1,455	1,341	(500)	(414)
Accumulated Other Comprehensive Loss, beginning balance	(7,950)	(6,417)	(19,853)	(79,096)
Accumulated Other Comprehensive Loss, before tax	(2,430)	20,994	92,541
Accumulated Other Comprehensive Loss, tax effect	897	(7,558)	(33,298)
Accumulated Other Comprehensive Loss, ending balance	$ (7,950)	$ (6,417)	$ (19,853)	$ (79,096)

Gross appreciation or the gross loss in value of the total of unsold available-for-sale securities (except when designated as a fair value hedge or which had been determined to have had an other than temporary decline in fair value below its amortized cost basis) attributable to the parent entity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 19

-URI http://asc.fasb.org/extlink&oid=6921628&loc=SL4569616-111683

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6921930&loc=SL4573702-111684

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 30

-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 AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

-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 AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 29

-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 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6921628&loc=SL4569643-111683

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- Definition

Gross appreciation or the gross loss in value of the total unsold securities, after tax, attributable to the parent entity.

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- Definition

Tax effect of the gross appreciation or the gross loss, net of reclassification adjustment, in the change in value of available for sale securities during the period that is attributable to the parent entity.

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Amounts recognized in other comprehensive income (but not yet recognized in net periodic benefit cost), including the net gain (loss) and net prior service cost (credit) arising during the period, which are attributable to the parent entity. Also includes reclassification adjustments out of other comprehensive income as a result of being recognized as components of net periodic benefit cost for the period.

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- Definition

The increase (decrease) to accumulated comprehensive income during the period related to benefit plans, after tax, attributable to the parent entity.

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Tax effects of the increase (decrease) to accumulated comprehensive income during the period related to benefit plans that is attributable to the parent entity.

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- Definition

Pre-tax change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges, net of reclassifications into earnings during the period, attributable to the parent entity. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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Net of tax effect change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges, that is attributable to the parent entity. The change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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Total tax effect of the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges that is attributable to the parent entity. The change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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- Definition

This element represents Other Comprehensive Income or Loss, Net of Tax, for the period attributable to the parent entity. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

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Tax effect of the change in accumulated other comprehensive income, that is, the tax effect on items included in other comprehensive income during the period that is attributable to the parent entity. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

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