Income Taxes (Schedule Of Changes In Gross Unrecognized Tax Benefits) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Beginning balance	$ 3,141	$ 4,873	$ 5,054
Additions based on tax position related to current year			678
(Reductions) additions for tax positions for prior years		(26)	711
Reductions due to tax settlements		(1,389)
Reductions due to statutes of limitations expiring	(19)	(317)	(1,570)
Ending balance	$ 3,122	$ 3,141	$ 4,873

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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

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-Glossary Unrecognized Tax Benefit

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

+ References

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

-Publisher FASB

-Name FASB Interpretation (FIN)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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

-Publisher FASB

-Name FASB Interpretation (FIN)

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-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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The gross amount of increases (decreases) in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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