Ordinary and Preference Shares - Additional Information (Detail) - Ordinary Shares [Member] - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
	Nov. 12, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Class Of Stock [Line Items]
Newly issued ordinary shares Issues	13,800,000	13,800,000	10,615,385	13,800,000	19,085,068
Newly issued ordinary price per share	$ 7.00
Proceeds from issuance of ordinary shares	$ 96.6
Underwriting discounts and other offering expenses	$ 6.2