Income Taxes - Reconciliation of Statutory Federal Income Tax Rate to Effective Consolidated Tax Rate (Detail)	4 Months Ended	8 Months Ended	12 Months Ended
Apr. 30, 2018	Dec. 31, 2017	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Income Tax Disclosure [Abstract]
U.S. federal statutory income tax rate	21.00%	35.00%	21.00%	21.00%	30.40%
State tax, net of federal effect			2.20%	1.10%	1.00%
Foreign tax rates differential			4.50%	5.00%	(2.30%)
Transition tax					9.0
Deferred tax remeasurement					(2.40%)
Non-deductible officers compensation			0.50%	1.10%
Excess tax benefit on stock-based compensation			(1.00%)	(3.10%)
Change in valuation allowance				(2.00%)	(2.30%)
Other			1.90%	(1.10%)	0.60%
Effective income tax rate			29.10%	22.00%	34.00%

Effective income tax rate reconciliation deferred taxes remeasurement percent.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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Percentage 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 changes in the valuation allowance for deferred tax assets.

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Percentage 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 applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to increase (decrease) from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act.

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