XML 73 R30.htm IDEA: XBRL DOCUMENT
v3.20.1

The Company and Summary of Significant Accounting Policies - Additional Information (Details) |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Aug. 28, 2019 | Sep. 30, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2019 USD ($) Gigabit / s | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Jan. 01, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Speed per second of high-speed interface technology of Bandwidth Engine ICs (in giga per second) | Gigabit / s |  |  |  | 10 |  |  |
Reverse stock split | 20 |  |  |  |  |  |
Maximum specific allowance as percentage of invoice value for problematic customer balances |  |  |  | 100.00% |  |  |
Allowance for doubtful accounts receivable |  |  | $ 0 | $ 0 | $ 0 |  |
Inventory reserves |  |  |  | 100,000 | 100,000 | $ 300,000 |
Impairment of goodwill |  | $ 400,000 | 12,900,000 | 420,000 | 12,856,000 |  |
Goodwill balance |  | $ 0 | 420,000 |  | 420,000 |  |
Accumulated deficit |  |  | (235,867,000) | $ (238,447,000) | (235,867,000) | (224,688,000) |
Payment terms |  |  |  | The Company sells its products both directly to customers and through distributors generally under agreements with payment terms typically 60 days or less |  |  |
Deferred revenue, revenue recognized |  |  |  | $ 300,000 |  |  |
Period payments due from customers |  |  |  | 60 days |  |  |
Revenue, practical expedient, financing component |  |  |  | true |  |  |
Right-of-use lease asset |  |  |  | $ 156,000 |  |  | $ 400,000
Lease liabilities |  |  |  | $ 166,000 |  |  | $ 400,000
Adjustments Due to ASC 606 | ASU 2014-09 |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Accumulated deficit |  |  | $ (220,000) |  | $ (220,000) | $ 230,000 |
Minimum |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Estimated useful lives of property and equipment |  |  |  | 3 years |  |  |
Estimated useful lives of long-lived assets |  |  |  | 3 years |  |  |
Maximum |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Estimated useful lives of property and equipment |  |  |  | 5 years |  |  |
Estimated useful lives of long-lived assets |  |  |  | 7 years |  |  |

X
- Definition Represents the maximum allowance for doubtful accounts provided for any problematic customer balances, expressed as a percentage of invoice value. + References No definition available. + Details
Name: | mosy_AllowanceForDoubtfulAccountsAsPercentageOfInvoiceValueForProblematicCustomerBalancesMaximum
Namespace Prefix: | mosy_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Represents the speed per second of the high-speed interface technology of Bandwidth Engine integrated circuits. + References No definition available. + Details
Name: | mosy_HighSpeedInterfaceTechnologySpeedPerSecond
Namespace Prefix: | mosy_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period in which customer payment due from invoice date when payment for product or service occurs within one year or less. + References No definition available. + Details
Name: | mosy_RevenuePracticalExpedientPeriodInWhichCustomerPaymentsDueFromInvoiceDate
Namespace Prefix: | mosy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Summary of significant accounting policies. + References No definition available. + Details
Name: | mosy_SummaryOfSignificantAccountingPoliciesLineItems
Namespace Prefix: | mosy_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of allowance for credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 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 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 Reference 4: 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
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045 + Details
Name: | us-gaap_ContractWithCustomerLiabilityRevenueRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details
Name: | us-gaap_Goodwill
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13854-109267 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266 + Details
Name: | us-gaap_GoodwillImpairmentLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116847112&loc=d3e4542-108314 + Details
Name: | us-gaap_InventoryWriteDown
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
Name: | us-gaap_OperatingLeaseLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
Name: | us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. + References Reference 1: 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(30)(a)(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(a)(4)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
Name: | us-gaap_RetainedEarningsAccumulatedDeficit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Description of payment terms in contract with customer. Includes, but is not limited to, timing of payment, existence of financing component, variability of consideration and constraint on variable consideration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 12 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130554-203045 + Details
Name: | us-gaap_RevenuePerformanceObligationDescriptionOfPaymentTerms
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Indicates (true false) whether practical expedient was elected not to adjust consideration for effect of financing component when transfer and customer payment for product or service occurs within one year or less. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130569-203045 + Details
Name: | us-gaap_RevenuePracticalExpedientFinancingComponent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:booleanItemType
Balance Type: | na
Period Type: | duration

X
- Definition Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB TOPIC 4.C) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770 + Details
Name: | us-gaap_StockholdersEquityNoteStockSplitConversionRatio1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis=us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201409Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |