Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Changes in unrecognized tax benefits
Balance at January 1	$ 1,015	$ 1,062	$ 1,304
Additions for tax positions of current year	0	0	53
Additions for tax positions of prior years	511	0	62
Reductions for tax positions of prior years	0	(32)	(281)
Expiration of statutes of limitations	(165)	(15)	(76)
Balance at December 31	$ 1,361	$ 1,015	$ 1,062

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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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The gross amount of decreases 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 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.

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