Fair Value Measurements (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Components of the change in auction rate securities
Proceeds from sale or call of auction rate securities	$ 9,938	$ 39,210
Total net realized (loss) gain recorded in investment income and other	(162)	875
Unrealized loss reclassified from accumulated other comprehensive income, included in realized (loss) gain above	$ (162)	$ (290)

Pre tax reclassification adjustment for gains or losses realized upon the sale of securities.

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+ Details