Concentration Risk - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Mar. 31, 2019
Customer Concentration Risk | Net Revenues
Concentration Risk [Line Items]
Concentration risk, percentage	78.00%	78.00%	75.00%	76.00%
Customer Concentration Risk | Net Revenues | Walmart
Concentration Risk [Line Items]
Concentration risk, percentage	49.00%	45.00%	44.00%	48.00%
Customer Concentration Risk | Net Revenues | Amazon.com
Concentration Risk [Line Items]
Concentration risk, percentage	17.00%	17.00%	20.00%	14.00%
Customer Concentration Risk | Net Revenues | Fred Meyer
Concentration Risk [Line Items]
Concentration risk, percentage	12.00%		11.00%	14.00%
Customer Concentration Risk | Net Revenues | D&H Distributing
Concentration Risk [Line Items]
Concentration risk, percentage		16.00%
Product Concentration Risk | Net Revenues | Microwave Ovens
Concentration Risk [Line Items]
Concentration risk, percentage	34.00%	40.00%	42.00%	45.00%
Product Concentration Risk | Net Revenues | Audio Products
Concentration Risk [Line Items]
Concentration risk, percentage	62.00%	56.00%	55.00%	50.00%
Credit Concentration Risk | Accounts Receivable | Customer One
Concentration Risk [Line Items]
Concentration risk, percentage			44.00%		47.00%
Credit Concentration Risk | Accounts Receivable | Customer Two
Concentration Risk [Line Items]
Concentration risk, percentage			30.00%		29.00%
Supplier Concentration Risk | Products for Resale
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%	67.00%	56.00%	61.00%
Supplier Concentration Risk | Products for Resale | Two Largest Factory Suppliers
Concentration Risk [Line Items]
Concentration risk, percentage	100.00%	87.00%	82.00%	85.00%