Supplemental Cash Flow Information (Schedule Of Supplemental Cash Flow Information) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Supplemental Cash Flow Information [Abstract]
Employee share-based compensation	$ 3,708	$ 2,951	$ 10,871	$ 8,359
Unrealized gains on available for sale securities, net			12	31
Cash paid for income taxes			69,930	31,742
Cash paid for interest			4,141	4,100
Cash received for stock option exercises			3,848	1,850
Cash received for employee stock purchase plan			$ 368	$ 271

The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The amount of cash paid for interest during the period.

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The cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards other than stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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The total cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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