The percentage of beneficial ownership if effective upon the applicable conversion date of debt instrument.

No definition available.

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- Definition

The period for outstanding balance of accounts receivable has not recorded an allowance for doubtful accounts pledged under the debt instrument conversion features, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The minimum amount of shares issuable for considering the change in conversion price of debt instrument if prior to the maturity date.

+ References

No definition available.

+ Details

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- Definition

The maximum amount of indebtedness subordinated by security interest and cash payment rights under the convertible debt instruments.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The number of shares of common stock that the holder of the debt instrument would receive if the debt was converted to common stock.

+ References

No definition available.

+ Details

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Namespace Prefix:	mosy_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the minimum beneficial ownership percentage which triggers, at the election of the holders, redemption of the notes.

+ References

No definition available.

+ Details

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Namespace Prefix:	mosy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.9)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=mosy_SeniorSecuredConvertibleNotesDueAugust152018Member
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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Convertible Notes (Details) - USD ($)		3 Months Ended	9 Months Ended
Convertible Notes (Details) - USD ($)	Mar. 14, 2016	Sep. 30, 2016	Sep. 30, 2016	Aug. 30, 2016
Convertible Notes
Interest Expense		$ 217,000	$ 464,000
Senior Secured Convertible Notes due August 15 2018
Convertible Notes
Stated interest rate (as a percent)	10.00%
Principal amount	$ 8,000,000
Conversion price (in dollars per share)	$ 0.90
Minimum ownership percentage triggering event for redemption of notes	40.00%
Redemption price (as a percent)	120.00%
Minimum amount of shares issuable if prior to maturity date of debt instrument for resetting conversion price	$ 1,000,000
Maximum amount of indebtedness subordinated by security interest and cash payment rights under debt instruments	$ 5,000,000
Debt issuance costs			100,000
Interest Expense			$ 23,000
Senior Secured Convertible Notes due August 15 2018 \| Minimum
Convertible Notes
Conversion price (in dollars per share)	$ 0.85
Percentage of beneficial ownership if effective upon conversion date of debt instrument	9.90%
Senior Secured Convertible Notes due August 15 2018 \| Maximum
Convertible Notes
Period for outstanding balance of accounts receivable has not recorded an allowance for doubtful accounts (in days)	90 days
Interest Note
Convertible Notes
Principal amount				$ 336,000
Conversion price (in dollars per share)		$ 0.85	$ 0.85
Number of shares issuable if notes converted to shares of common stock			9,806,499