Cost incurred for Storage fees and other services.

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

The amount of cash paid for non-recurring engineering fees during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

This element represents the reimbursement of amount paid towards engineering and quality control services performed during the reporting period.

+ References

No definition available.

+ Details

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Namespace Prefix:	SMDM_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The average gross profit margin on sales to related party.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

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The effective interest rate during the reporting period.

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- Definition

Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

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- Definition

Amount of the required periodic payments of both interest and principal.

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- Definition

The amount for notes payable (written promise to pay), due to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Period Type:	instant

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Balance Type:	debit
Period Type:	duration

- 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.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_WarehouseMember
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Balance Type:
Period Type:

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Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=SMDM_TwoYearTermNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=SMDM_LIBORRateMember
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Data Type:	na
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Period Type:

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Related Party Transactions (Details Narrative) - USD ($)			12 Months Ended
	Aug. 01, 2017	Jun. 22, 2017	Mar. 31, 2019	Mar. 31, 2018
Related Party Transaction [Line Items]
Due from related parties, current			$ 300,000	$ 1,200,000
Warehouse Facility [Member]
Related Party Transaction [Line Items]
Revenue from related parties			$ 400,000	$ 600,000
Related party gross margin percentage			22.50%	24.60%
Revolving Credit Facility [Member]
Related Party Transaction [Line Items]
Line of credit facility interest rate			0.75%
Revolving Credit Facility [Member] \| Two Year Term Note [Member]
Related Party Transaction [Line Items]
Proceeds from line of credit		$ 1,000,000
Line of credit facility, maximum amount outstanding during period		800,000
Line of credit facility, periodic payment	$ 123,000	125,000
Repayments of lines of credit		$ 800,000
Debt instrument due date		Aug. 01, 2017
Accrued interest rate percentage	6.00%
Revolving Credit Facility [Member] \| Two Year Term Note [Member] \| Prime Rate [Member]
Related Party Transaction [Line Items]
Line of credit facility interest rate		1.75%
Revolving Credit Facility [Member] \| Two Year Term Note [Member] \| LIBOR Rate [Member]
Related Party Transaction [Line Items]
Line of credit facility interest rate		3.75%
Starlight Marketing Development, Ltd [Member]
Related Party Transaction [Line Items]
Due to related parties		$ 1,900,000
Notes payable, related parties, current			$ 800,000
Reimbursement Paid			400,000	$ 300,000
Payments for non recurring engineering fees			21,000	43,000
Winglight Pacific Ltd [Member]
Related Party Transaction [Line Items]
Revenue from related parties			$ 1,200,000	$ 1,500,000
Related party gross margin percentage			30.10%	21.80%
Merrygain Holding Co., Ltd [Member]
Related Party Transaction [Line Items]
Cost incurred for Storage fees and other services			$ 100,000	$ 200,000