Fair Value Measurements (Schedule Of Items Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands	Aug. 31, 2020	Feb. 29, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	$ 852,767	$ 273,203
Mutual fund investments	23,424	22,668
Total assets at fair value	$ 876,266	$ 295,871
Percent of total assets at fair value	100.00%	100.00%
Percent of total assets	4.10%	1.40%
Total liabilities at fair value	$ (9,741)	$ (23,992)
Percent of total liabilities	0.10%	0.10%
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	$ 852,767	$ 273,203
Mutual fund investments	23,424	22,668
Total assets at fair value	$ 876,191	$ 295,871
Percent of total assets at fair value	100.00%	100.00%
Percent of total assets	4.10%	1.40%
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
Total assets at fair value	$ 75	$ 0
Percent of total assets at fair value	0.00%	0.00%
Percent of total assets	0.00%	0.00%
Total liabilities at fair value	$ (9,741)	$ (23,992)
Percent of total liabilities	0.10%	0.10%
Designated As Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative instruments designated as hedges	$ 75
Liabilities: Derivative instruments	(9,741)	$ (23,992)
Designated As Hedging Instrument | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative instruments designated as hedges	0
Liabilities: Derivative instruments	0	0
Designated As Hedging Instrument | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative instruments designated as hedges	75
Liabilities: Derivative instruments	$ (9,741)	$ (23,992)