XML 39 R67.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Income Taxes - Additional Information (Detail) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Operating Loss Carryforwards [Line Items] |  |  |  |
Valuation allowances related to U.S. based deferred taxes |  | $ 11,300,000 us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount | $ 15,600,000 us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount |
Valuation allowance | 90,774,000 us-gaap_DeferredTaxAssetsValuationAllowance | 90,774,000 us-gaap_DeferredTaxAssetsValuationAllowance | 79,458,000 us-gaap_DeferredTaxAssetsValuationAllowance |
Statutory federal income tax rate |  | 34.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate | 34.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate | 34.00%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
Internal revenue code related to annual use of operating loss carry forwards |  | annual use of the Company’s net operating loss and research and development credit carryforwards may be limited in the event a cumulative change in ownership of more than 50% occurs within a three-year period |  |
Internal revenue code, cumulative change in ownership (percent) |  | 50.00%nvtl_InternalRevenueCodeOwnershipPercentageChange |  |
Uncertain income tax position unrecognized |  | less than a 50% likelihood |  |
Settlements and lapses in statutes of limitations |  | 61,000 nvtl_RecognizedTaxBenefitResultingFromLapseOfApplicableStatuteOfLimitations | 71,000 nvtl_RecognizedTaxBenefitResultingFromLapseOfApplicableStatuteOfLimitations |
Associated interest due to expiration of the applicable statutes of limitations for certain tax years |  | 0 us-gaap_UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense | 236,000 us-gaap_UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense |
Total liability for unrecognized tax benefits included other long-term liabilities |  | 0 us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease | 61,000 us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease |
Interest and penalties related to unrecognized tax benefits in the provision for income taxes |  | 0 us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense |  |
Uncertain tax liability | 61,000 nvtl_IncreaseDecreaseInUncertainTaxPositionsDueToReclassificationToLiability |  |  |
Domestic Country |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |
Valuation allowance | 86,000,000 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_IncomeTaxAuthorityAxis = us-gaap_DomesticCountryMember | 86,000,000 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_IncomeTaxAuthorityAxis = us-gaap_DomesticCountryMember | 74,700,000 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_IncomeTaxAuthorityAxis = us-gaap_DomesticCountryMember |
Net operating loss carryforwards | 174,300,000 us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_DomesticCountryMember | 174,300,000 us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_DomesticCountryMember |  |
Net operating loss expiration dates |  | 2029 through 2034 |  |
Research and development tax credit carryforwards | 4,300,000 us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch / us-gaap_IncomeTaxAuthorityAxis = us-gaap_DomesticCountryMember | 4,300,000 us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch / us-gaap_IncomeTaxAuthorityAxis = us-gaap_DomesticCountryMember |  |
Tax credits expiration dates |  | 2027 through 2034 |  |
Foreign Country |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |
Valuation allowance | 4,800,000 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_IncomeTaxAuthorityAxis = us-gaap_ForeignCountryMember | 4,800,000 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_IncomeTaxAuthorityAxis = us-gaap_ForeignCountryMember | 4,700,000 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_IncomeTaxAuthorityAxis = us-gaap_ForeignCountryMember |
State and Local Jurisdiction |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |
Net operating loss carryforwards | 67,100,000 us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember | 67,100,000 us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember |  |
Net operating loss expiration dates |  | 2017 through 2034 |  |
Research and development tax credit carryforwards | $ 5,400,000 us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember | $ 5,400,000 us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember |  |

X
- Definition Deferred Tax Assets Tax Credit Carryforwards Research Expiration Dates + References No definition available. + Details
Name: | nvtl_DeferredTaxAssetsTaxCreditCarryforwardsResearchExpirationDates
Namespace Prefix: | nvtl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Increase Decrease In Uncertain Tax Positions Due To Reclassification To Liability + References No definition available. + Details
Name: | nvtl_IncreaseDecreaseInUncertainTaxPositionsDueToReclassificationToLiability
Namespace Prefix: | nvtl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Internal Revenue Code Ownership Percentage Change + References No definition available. + Details
Name: | nvtl_InternalRevenueCodeOwnershipPercentageChange
Namespace Prefix: | nvtl_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Internal Revenue Code Ownership Percentage Change Description + References No definition available. + Details
Name: | nvtl_InternalRevenueCodeOwnershipPercentageChangeDescription
Namespace Prefix: | nvtl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Operating Loss Carryforwards Expiration Date One + References No definition available. + Details
Name: | nvtl_OperatingLossCarryforwardsExpirationDateOne
Namespace Prefix: | nvtl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Recognized Tax Benefit Resulting From Lapse Of Applicable Statute Of Limitations + References No definition available. + Details
Name: | nvtl_RecognizedTaxBenefitResultingFromLapseOfApplicableStatuteOfLimitations
Namespace Prefix: | nvtl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Uncertain income tax position unrecognized. + References No definition available. + Details
Name: | nvtl_UncertainIncomeTaxPositionUnrecognized
Namespace Prefix: | nvtl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 + Details
Name: | us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 + Details
Name: | us-gaap_DeferredTaxAssetsValuationAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + 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 S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: 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_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 + Details
Name: | us-gaap_OperatingLossCarryforwards
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_OperatingLossCarryforwardsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
Name: | us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of interest expense for an underpayment of 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 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
Name: | us-gaap_UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The net amount of all increases and decreases in unrecognized tax benefits for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
Name: | us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of the change in the period in the valuation allowance for a specified deferred tax asset. + References Reference 1: 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=21917399&loc=d3e32123-109318 + Details
Name: | us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_DomesticCountryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_ForeignCountryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_StateAndLocalJurisdictionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |