Contract Liabilities (Details) - USD ($)	Dec. 31, 2019	Mar. 31, 2019
Short-term contract liabilities [Abstract]
Customer allowances earned	$ 10,570,000	$ 12,755,000
Customer core returns accruals	13,088,000	3,933,000
Customer deposits	1,359,000	2,674,000
Accrued core payment, net	7,936,000	11,237,000
Total short-term contract liabilities	32,953,000	30,599,000
Long-term contract liabilities [Abstract]
Customer core returns accruals	46,467,000	25,722,000
Accrued core payment, net	9,009,000	15,167,000
Total long-term contract liabilities	$ 55,476,000	$ 40,889,000