Income Taxes - Additional Information (Detail) - USD ($)		1 Months Ended	3 Months Ended		9 Months Ended
	Dec. 22, 2017	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.S. federal statutory corporate tax rate		35.00%	21.00%	31.50%	21.00%	31.50%
Income tax provision (benefit)			$ 19,648,000	$ 32,208,000	$ (20,225,000)	$ 36,607,000
Effective income tax rate			30.50%	70.60%	(12.30%)	32.70%
Measurement period	1 year
Income tax expense			$ 0		$ 0
Excess tax benefits from stock-based awards			$ 1,700,000	$ 3,200,000	$ 68,500,000	$ 24,500,000
Potential repatriation of foreign subsidiary earnings					100.00%