Income Taxes (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Tax Benefits in Shareholders' Equity
Income tax benefits arising from compensation expense for tax purposes in excess of amounts recognized for financial statement purposes	$ 22,835	$ 63,558	$ 66,448

The aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions.

No definition available.

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