Stockholders' Equity - Narrative (Details) shares in Millions, $ in Millions	12 Months Ended
	Mar. 31, 2020 USD ($) vote shares	Mar. 31, 2019 USD ($) shares	May 23, 2019 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock votes per share | vote	1
Share repurchase program, remaining authorized repurchase amount	$ 484.8
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share repurchase program, remaining authorized repurchase amount			$ 1,310.0
Repurchase of common stock (in shares) | shares	2.5	5.1
Share repurchase program, amount authorized	$ 173.4	$ 239.8