Net Earnings Per Share (Basic And Dilutive Net Earnings Per Share Reconciliations) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Aug. 31, 2014	Aug. 31, 2013	Aug. 31, 2014	Aug. 31, 2013
Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Line Items]
Net earnings	$ 154,518	$ 140,274	$ 324,171	$ 286,925
Weighted average common shares outstanding	218,180	223,610	219,224	224,114
Weighted average common shares and dilutive potential common shares	221,070	227,634	222,351	228,093
Basic net earnings per share	$ 0.71	$ 0.63	$ 1.48	$ 1.28
Diluted net earnings per share	$ 0.70	$ 0.62	$ 1.46	$ 1.26
Stock Options [Member]
Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Line Items]
Dilutive potential common shares	2,269	3,319	2,520	3,257
Stock-Settled Restricted Stock Units [Member]
Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Line Items]
Dilutive potential common shares	621	705	607	722

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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