Revenue Recognition - Schedule of Contract Assets and Contract Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Contract Asset
Balance as of March 31, 2018	$ 10,441	$ 11,251
Change in estimate of sales returns	36,223
Actual returns	(37,033)
Balance as of March 31, 2019	10,441
Contract Liability
Balance as of March 31, 2018	24,787	$ 23,156
Change in estimate of sales returns	120,102
Actual returns	(118,471)
Balance as of March 31, 2019	$ 24,787