Risks and Uncertainties - Additional Information (Detail) - USD ($)	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Unusual Risk Or Uncertainty [Line Items]
Allowance for doubtful accounts	$ 2,000	$ 6,000
Cash, cash equivalents and restricted cash balances in excess of FDIC-insured limits	7,600,000	24,800,000
Maximum
Unusual Risk Or Uncertainty [Line Items]
Cash and restricted cash deposit	$ 250,000	$ 250,000
Customer Concentration Risk \| Net Revenues
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	79.00%	84.00%
Customer Concentration Risk \| Net Revenues \| Walmart
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	50.00%	62.00%
Customer Concentration Risk \| Net Revenues \| Amazon.com
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	16.00%	11.00%
Customer Concentration Risk \| Net Revenues \| Fred Meyer
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	13.00%	11.00%
Product Concentration Risk \| Net Revenues
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	40.00%	69.00%
Product Concentration Risk \| Net Revenues \| Microwave Ovens
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	39.00%	63.00%
Product Concentration Risk \| Net Revenues \| Toaster Ovens
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	1.00%
Product Concentration Risk \| Net Revenues \| Compact Refrigerators
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		6.00%
Product Concentration Risk \| Net Revenues \| Audio Products
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	57.00%	30.00%
Credit Concentration Risk \| Accounts Receivable \| Walmart
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	47.00%	64.00%
Credit Concentration Risk \| Accounts Receivable \| Amazon.com
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	29.00%	21.00%
Supplier Concentration Risk \| Products for Resale \| Two Largest Factory Suppliers
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		93.00%
Supplier Concentration Risk \| Products for Resale \| Two Largest Factory Suppliers \| CHINA
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	90.00%
Supplier Concentration Risk \| Products for Resale \| Supplier One [Member]
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		59.00%
Supplier Concentration Risk \| Products for Resale \| Supplier One [Member] \| CHINA
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	71.00%
Supplier Concentration Risk \| Products for Resale \| Supplier Two [Member]
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		34.00%
Supplier Concentration Risk \| Products for Resale \| Supplier Two [Member] \| CHINA
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	19.00%

Cash, cash equivalents, restricted cash and restricted cash equivalents in excess of FDIC insured limits.

No definition available.

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13531-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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