XML 67 R68.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Reconciliation of Income Tax Expense on Pretax Income at Statutory Rate and Income Tax Expense (Detail) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Reconciliation Of Income Taxes [Line Items] |  |  |
Cayman statutory rate | $ 0 simo_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtUnifiedStatutoryIncomeTaxRate | $ 0 simo_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtUnifiedStatutoryIncomeTaxRate | $ 0 simo_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtUnifiedStatutoryIncomeTaxRate
Tax on pretax income at statutory rate | 15,727 us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate | 6,788 us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate | 8,142 us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate
Tax-exempt income | (2,573)us-gaap_IncomeTaxReconciliationTaxExemptIncome | (4,325)us-gaap_IncomeTaxReconciliationTaxExemptIncome | (5,149)us-gaap_IncomeTaxReconciliationTaxExemptIncome
Permanent differences | (396)simo_IncomeTaxReconciliationPermanentDifferences | 1,730 simo_IncomeTaxReconciliationPermanentDifferences | 861 simo_IncomeTaxReconciliationPermanentDifferences
Temporary differences | (344)simo_TemporaryDifferences | 1,732 simo_TemporaryDifferences | (2,290)simo_TemporaryDifferences
Alternative minimum tax | 1,170 simo_IncomeTaxReconciliationAlternativeMinimumTax | 2,203 simo_IncomeTaxReconciliationAlternativeMinimumTax | 4,340 simo_IncomeTaxReconciliationAlternativeMinimumTax
Income tax (10%) on undistributed earnings | 2,491 simo_IncomeTaxReconciliationInUndistributedEarnings | 3,396 simo_IncomeTaxReconciliationInUndistributedEarnings | 2,631 simo_IncomeTaxReconciliationInUndistributedEarnings
Net changes in income tax credit | (899)us-gaap_IncomeTaxReconciliationTaxCreditsInvestment | 708 us-gaap_IncomeTaxReconciliationTaxCreditsInvestment | 5,518 us-gaap_IncomeTaxReconciliationTaxCreditsInvestment
Net changes in valuation allowance of deferred income tax assets | 733 us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance | (2,364)us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance | (3,879)us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance
Net operating loss carryforwards | (1,298)simo_IncomeTaxReconciliationUtilizationOfOperatingLossCarryforwards | (189)simo_IncomeTaxReconciliationUtilizationOfOperatingLossCarryforwards | 604 simo_IncomeTaxReconciliationUtilizationOfOperatingLossCarryforwards
Liabilities related to unrealized tax benefits | 91 us-gaap_IncomeTaxReconciliationOtherAdjustments | (39)us-gaap_IncomeTaxReconciliationOtherAdjustments | 832 us-gaap_IncomeTaxReconciliationOtherAdjustments
Adjustment of prior years' taxes and others | 1,399 us-gaap_IncomeTaxReconciliationPriorYearIncomeTaxes | 132 us-gaap_IncomeTaxReconciliationPriorYearIncomeTaxes | (4,494)us-gaap_IncomeTaxReconciliationPriorYearIncomeTaxes
Income tax expense | $ 16,101 us-gaap_IncomeTaxExpenseBenefit | $ 9,772 us-gaap_IncomeTaxExpenseBenefit | $ 7,116 us-gaap_IncomeTaxExpenseBenefit

X
- Definition Income Tax Reconciliation Alternative Minimum Tax + References No definition available. + Details
Name: | simo_IncomeTaxReconciliationAlternativeMinimumTax
Namespace Prefix: | simo_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Income Tax Reconciliation Income Tax Expense (Benefit) at Unified Statutory Income Tax Rate + References No definition available. + Details
Name: | simo_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtUnifiedStatutoryIncomeTaxRate
Namespace Prefix: | simo_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Income Tax Reconciliation In Undistributed Earnings + References No definition available. + Details
Name: | simo_IncomeTaxReconciliationInUndistributedEarnings
Namespace Prefix: | simo_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Income Tax Reconciliation, Permanent Differences + References No definition available. + Details
Name: | simo_IncomeTaxReconciliationPermanentDifferences
Namespace Prefix: | simo_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Income Tax Reconciliation, Utilization of Operating Loss Carryforwards + References No definition available. + Details
Name: | simo_IncomeTaxReconciliationUtilizationOfOperatingLossCarryforwards
Namespace Prefix: | simo_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | simo_ReconciliationOfIncomeTaxesLineItems
Namespace Prefix: | simo_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the temporary tax differences. + References No definition available. + Details
Name: | simo_TemporaryDifferences
Namespace Prefix: | simo_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Income Tax Expense (or Benefit) -URI http://asc.fasb.org/extlink&oid=6515339 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 + Details
Name: | us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=37586315&loc=d3e32123-109318 + Details
Name: | us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Subparagraph 2 -Article 4 + Details
Name: | us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationOtherAdjustments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to revisions of previously reported income tax expense (benefit). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationPriorYearIncomeTaxes
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to investment tax credit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationTaxCreditsInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income (loss) exempt from income taxes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 + Details
Name: | us-gaap_IncomeTaxReconciliationTaxExemptIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration