Risks and Uncertainties - Additional Information (Detail) - USD ($)	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Unusual Risk Or Uncertainty [Line Items]
Allowance for doubtful accounts	$ 6,000	$ 4,000
Cash, cash equivalents and restricted cash balances in excess of FDIC-insured limits	24,500,000	27,000,000
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	84.00%	83.00%
Customer Concentration Risk \| Net Revenues \| Amazon.com
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	11.00%
Customer Concentration Risk \| Net Revenues \| Walmart
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	62.00%	53.00%
Customer Concentration Risk \| Net Revenues \| Fred Meyer
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	11.00%	17.00%
Customer Concentration Risk \| Net Revenues \| Funai
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		13.00%
Product Concentration Risk \| Net Revenues
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	69.00%	82.00%
Product Concentration Risk \| Net Revenues \| Microwave Ovens
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	63.00%	71.00%
Product Concentration Risk \| Net Revenues \| Compact Refrigerators
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	6.00%	11.00%
Product Concentration Risk \| Net Revenues \| Audio Products
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	30.00%	18.00%
Credit Concentration Risk \| Trade Accounts Receivable, Net of Specific Reserves \| Amazon.com
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	21.00%
Credit Concentration Risk \| Trade Accounts Receivable, Net of Specific Reserves \| Walmart
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	64.00%	91.00%
Credit Concentration Risk \| Trade Accounts Receivable, Net of Specific Reserves \| Fred Meyer
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		0.00%
Supplier Concentration Risk [Member] \| Products for Resale \| Two Largest Factory Suppliers
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	93.00%	91.00%
Supplier Concentration Risk [Member] \| Products for Resale \| Supplier One [Member]
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	59.00%	75.00%
Supplier Concentration Risk [Member] \| Products for Resale \| Supplier Two [Member]
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	34.00%	16.00%

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://www.xbrl.org/2003/role/presentationRef
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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Balance Type:	credit
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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

+ Details

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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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