Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Feb. 29, 2020	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2017
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			$ 32,700
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount			$ 20,800
Federal statutory income tax rate	21.00%	21.00%	32.70%
2017 Tax Act Federal Statutory Income Tax Rate			21.00%
Unrecognized tax benefits, gross	$ 30,865	$ 30,270	$ 28,685	$ 29,955
Unrecognized tax benefits that would impact effective tax rate, if recognized	9,200	10,700	9,600
Accrued interest	$ 4,000	$ 3,200	$ 2,800

2017 Tax Act Federal Statutory Income Tax Rate

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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