Net Income Per Share - Summary of Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
NET INCOME PER SHARE-BASIC:
Net income attributable to ADS	$ 18,273	$ 11,694
Accretion of Redeemable noncontrolling interest	(362)
Dividends to Redeemable convertible preferred stockholders	(425)	(371)
Dividends paid to unvested restricted stockholders	(30)	(6)
Net income available to common stockholders and participating securities	17,456	11,317
Undistributed income allocated to participating securities	(1,524)	(969)
Net income available to common stockholders - Basic	$ 15,932	$ 10,348
Weighted average number of common shares outstanding - Basic	54,071	53,623
Net income per common share - Basic	$ 0.29	$ 0.19
NET INCOME PER SHARE-DILUTED:
Net income available to common stockholders - Diluted	$ 15,932	$ 10,348
Weighted average number of common shares outstanding - Basic	54,071	53,623
Assumed exercise of stock options	857	1,377
Weighted average number of common shares outstanding - Diluted	54,928	55,000
Net income per common share - Diluted	$ 0.29	$ 0.19
Potentially dilutive securities excluded as anti-dilutive	6,444	6,688