Concentration Risk - Additional Information (Detail)	3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2018
Customer Concentration Risk | Net Revenues
Concentration Risk [Line Items]
Concentration risk, percentage	89.00%	92.00%	80.00%	84.00%
Customer Concentration Risk | Net Revenues | Walmart
Concentration Risk [Line Items]
Concentration risk, percentage	51.00%	61.00%	49.00%	62.00%
Customer Concentration Risk | Net Revenues | Amazon.com
Concentration Risk [Line Items]
Concentration risk, percentage	23.00%	17.00%	17.00%	11.00%
Customer Concentration Risk | Net Revenues | Fred Meyer
Concentration Risk [Line Items]
Concentration risk, percentage	15.00%	14.00%	14.00%	11.00%
Product Concentration Risk | Net Revenues | Microwave Ovens
Concentration Risk [Line Items]
Concentration risk, percentage	30.00%	59.00%	40.00%	63.00%
Product Concentration Risk | Net Revenues | Audio Products
Concentration Risk [Line Items]
Concentration risk, percentage	67.00%	33.00%	56.00%	28.00%
Credit Concentration Risk | Accounts Receivable | Customer One
Concentration Risk [Line Items]
Concentration risk, percentage			53.00%		64.00%
Credit Concentration Risk | Accounts Receivable | Customer Two
Concentration Risk [Line Items]
Concentration risk, percentage			46.00%		21.00%
Supplier Concentration Risk | Products for Resale
Concentration Risk [Line Items]
Concentration risk, percentage	86.00%	68.00%	72.00%	63.00%
Supplier Concentration Risk | Products for Resale | Two Largest Factory Suppliers
Concentration Risk [Line Items]
Concentration risk, percentage	96.00%	97.00%	90.00%	93.00%