Income Tax (Summary Of The Activity Related To Unrecognized Tax Benefits) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax [Abstract]
Unrecognized tax benefits - gross beginning balance	$ 1,974	$ 8,058	$ 11,412
Gross increases - prior period tax positions	112
Gross increases - current period tax positions		151	405
Settlements		(6,235)	(3,189)
Statute of limitations lapse			(570)
Unrecognized tax benefits - gross ending balance	$ 2,086	$ 1,974	$ 8,058

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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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-Publisher FASB

-Name Accounting Standards Codification

-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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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

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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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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