v2.4.0.6
Summary of Significant Accounting Policies Realized Gain (Loss) on Short-Term Investments (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Cash, Cash Equivalents, and Short-term Investments [Abstract]      
Available-for-sale Securities, Gross Realized Gains $ 37 $ 64 $ 181
Available-for-sale Securities, Gross Realized Losses (274) (234) (104)
Available-for-sale Securities, Gross Realized Gain (Loss) $ (237) $ (170) $ 77