Income Taxes - Unrecognized Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Reconciliation of the beginning and ending amounts of total unrecognized tax benefits
Balance at the beginning of the period	$ 17,638	$ 10,942	$ 9,594
Gross increase related to current fiscal year tax positions	2,242	1,153	1,027
Gross increase related to prior fiscal year tax positions	8,566	8,152	3,282
Settlements		(246)	(1,157)
Gross decrease related to prior fiscal year tax positions	(1,215)
Lapse of statute of limitations	(1,961)	(2,363)	(1,804)
Balance at the end of the period	$ 25,270	$ 17,638	$ 10,942