Fair Value Measurements (Schedule Of Items Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands	Feb. 28, 2019	Feb. 28, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	$ 372,448	$ 276,894
Mutual fund investments	19,263	19,429
Derivative instruments	1,844	12,127
Total assets at fair value	$ 393,555	$ 308,450
Percent of total assets at fair value	100.00%	100.00%
Percent of total assets	2.10%	1.80%
Derivative instruments	$ (6,120)	$ (99)
Total liabilities at fair value	$ (6,120)	$ (99)
Percent of total liabilities	0.00%	0.00%
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	$ 372,448	$ 276,894
Mutual fund investments	19,263	19,429
Derivative instruments	0	0
Total assets at fair value	$ 391,711	$ 296,323
Percent of total assets at fair value	99.50%	96.10%
Percent of total assets	2.10%	1.70%
Derivative instruments	$ 0	$ 0
Total liabilities at fair value	$ 0	$ 0
Percent of total liabilities	0.00%	0.00%
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	$ 0	$ 0
Mutual fund investments	0	0
Derivative instruments	1,844	12,127
Total assets at fair value	$ 1,844	$ 12,127
Percent of total assets at fair value	0.50%	3.90%
Percent of total assets	0.00%	0.10%
Derivative instruments	$ (6,120)	$ (99)
Total liabilities at fair value	$ (6,120)	$ (99)
Percent of total liabilities	0.00%	0.00%