Consolidated Statements Of Equity (Parenthetical) (USD $) In Thousands, except Share data	9 Months Ended
Sep. 30, 2011
Consolidated Statement Of Equity (Parenthetical) [Abstract]
Unrealized holding gain on investments, tax	$ 149
Reclassification adjustment for gain reported in income, tax	$ 84
Sale of stock, shares	445,004
Repurchase of stock, shares	44,165
Equity compensation plan, shares	14,176
Exercise of stock options, shares	375,023

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Tax effect on the reclassification adjustment for gains or losses realized upon the sale of securities during the period.

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Tax effect on gross appreciation or the gross loss in value of the total of unsold securities during the period being reported on.

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Net number of share options (or share units) granted during the period.

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Number of new stock issued during the period.

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Number of share options (or share units) exercised during the current period.

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