Risks and Uncertainties - Additional Information (Detail) - USD ($)	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Unusual Risk Or Uncertainty [Line Items]
Allowance for doubtful accounts	$ 4,000	$ 2,000
Cash, cash equivalents and restricted cash balances in excess of FDIC-insured limits	6,000,000	7,600,000
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	80.00%	79.00%
Customer Concentration Risk \| Net Revenues \| Walmart
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	44.00%	50.00%
Customer Concentration Risk \| Net Revenues \| Amazon.com
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	25.00%	16.00%
Customer Concentration Risk \| Net Revenues \| Fred Meyer
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	11.00%	13.00%
Product Concentration Risk \| Net Revenues
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	35.00%	39.00%
Product Concentration Risk \| Net Revenues \| Audio Products
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	61.00%	57.00%
Credit Concentration Risk \| Accounts Receivable \| Walmart
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	45.00%	47.00%
Credit Concentration Risk \| Accounts Receivable \| Amazon.com
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	45.00%	29.00%
Supplier Concentration Risk \| Products for Resale \| Two Largest Factory Suppliers
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		90.00%
Supplier Concentration Risk \| Products for Resale \| Two Largest Factory Suppliers \| CHINA
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	87.00%
Supplier Concentration Risk \| Products for Resale \| Supplier One [Member]
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		71.00%
Supplier Concentration Risk \| Products for Resale \| Supplier One [Member] \| CHINA
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	50.00%
Supplier Concentration Risk \| Products for Resale \| Supplier Two [Member]
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage		19.00%
Supplier Concentration Risk \| Products for Resale \| Supplier Two [Member] \| CHINA
Unusual Risk Or Uncertainty [Line Items]
Concentration risk, percentage	37.00%

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

No definition available.

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance for credit loss on accounts receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446

+ Details

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Balance Type:	credit
Period Type:	instant

- 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=118260190&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ 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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