Net Income Per Share and Stockholders' Equity - Summary of Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
NET INCOME PER SHARE—BASIC:
Net income (loss) attributable to ADS	$ 70,466	$ (226,356)
Dividends to redeemable convertible preferred stockholders	(1,366)	(6,841)
Dividends paid to unvested restricted stockholders	(2)	(328)
Net income (loss) available to common stockholders and participating securities	69,098	(233,525)
Undistributed income allocated to participating securities	(11,242)
Net income (loss) available to common stockholders – Basic	$ 57,856	$ (233,525)
Weighted average number of common shares outstanding – Basic	69,380	57,576
Net income (loss) per common share – Basic	$ 0.83	$ (4.06)
NET INCOME PER SHARE—DILUTED:
Net income (loss) available to common stockholders – Diluted	$ 57,856	$ (233,525)
Weighted average number of common shares outstanding – Basic	69,380	57,576
Weighted average number of common shares outstanding – Diluted	70,126	57,576
Net income (loss) per common share – Diluted	$ 0.83	$ (4.06)
Potentially dilutive securities excluded as anti-dilutive	15,161	10,806
Exercise of Stock Options [Member]
NET INCOME PER SHARE—DILUTED:
Dilutive securities	573
Restricted Stock [Member]
NET INCOME PER SHARE—DILUTED:
Dilutive securities	173