CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net gains on cash flow hedging instruments, deferred income taxes	$ (2,107)	$ (382)	$ (3,849)	$ (3,580)
Reclassification adjustment for losses on cash flow hedging instruments included in net income, deferred income taxes				(10)
Pension liability adjustments, deferred income taxes	(3,691)	4,130	(2,744)	(6,965)
Unrealized gains (losses) on marketable securities, deferred income taxes	7	(3)	9	(2)
Reclassification adjustment for gain on marketable securities, deferred income taxes				$ 1

Tax effects of the increase (decrease) to accumulated comprehensive income during the period related to benefit plans. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e640-108580

Reference 3: 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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- Definition

Tax effect on the reclassification adjustment for gains or losses realized upon the sale of securities during the period.

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- Definition

Tax effect on reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

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Tax effect on the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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- Definition

Tax effect on gross appreciation or the gross loss in value of the total of unsold securities during the period being reported on.

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