Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Changes in the reserve for income taxes, excluding interest and penalties
Beginning Balance of reserve for income taxes	$ 4,181	$ 5,355
Gross amounts of increases in unrecognized tax benefits as a result of tax positions taken in prior periods	7	420
Gross amounts of increases in unrecognized tax benefits as a result of tax positions taken in the current period	937	606
Gross amounts of decreases in unrecognized tax benefits relating to settlements with taxing authorities	(192)	(2,122)
Gross amounts of decreases in unrecognized tax benefits as a result of the expiration of the applicable statutes of limitations	(785)	(78)
Ending balance of reserve for income taxes	$ 4,148	$ 4,181

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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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