Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Reconciliation of Unrecognized Tax Benefits
Balance at beginning of year	$ 44,722	$ 48,669
Additions for tax positions for prior years	0
Additions based on tax positions related to the current year	3,291	4,092
Reductions for tax positions of prior years	(2,964)	(8,039)
Settlements	0
Balance at end of year	$ 45,049	$ 44,722

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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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