Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands, shares in Millions	3 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Income Taxes [Line Items]
Effective income tax rate	(10.90%)	29.70%
Discrete income tax expense	$ 60,700
Additional stock-based compensation expense	$ 1,841	$ 1,559
Special Dividend [Member]
Income Taxes [Line Items]
Dividend payable date	Jun. 14, 2019
Employee Stock Ownership Plan (ESOP) [Member]
Income Taxes [Line Items]
Non-deductible stock appreciation of total stock-based compensation expense	$ 237,600
Effective tax rate reduced by discrete event	(29.60%)
Employee Stock Ownership Plan (ESOP) [Member] \| Special Dividend [Member]
Income Taxes [Line Items]
Shares allocated from the ESOP from discrete event	11.6
Dividend payable date	Jun. 14, 2019
Additional stock-based compensation expense	$ 246,800

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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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 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 equity-based compensation costs.

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The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested.

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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 nondeductible equity-based compensation costs.

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Discrete income tax expense (benefit).

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Income taxes.

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