Document And Entity Information
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo
2019
Note To Financial Statement Details Textual
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree
2020
Significant Accounting Policies
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour
2021
Note 2 - Revenue Information
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive
2022
Due within one year, amortized cost
Note 3 - Earnings (Loss) Per Share
Note 4 - Marketable Securities
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]
Due within one year, estimated fair value
Note 5 - Intangible Assets
Due after one year through five years, estimated fair value
Note 6 - Inventories
Note 7 - Share-based Compensation
us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities
Tax benefit from exercise of stock options
Note 8 - Shareholders' Equity
Note 9 - Fair Value Measurements
Income Tax Disclosure [Text Block]
Note 2 - Revenue Information - Revenue by Product Group (Details)
Unrealized gain (loss) on available-for-sale securities, net of tax
Note 3 - Earnings (Loss) Per Share - Computation of Basic and Diluted Earnings per Common Share (Details)
Note 4 - Marketable Securities - Available-for-sale Securities by Major Security Type (Details)
Other assets
Share-based compensation expense
Stock-based compensation expense
Note 4 - Marketable Securities - Maturities of Available-for-sale Securities (Details)
us-gaap_LiabilitiesCurrent
Total current liabilities
Note 4 - Marketable Securities - Available-for-sale Marketable Securities in Gross Unrealized Loss Position (Details)
Note 5 - Intangible Assets - Intangible Assets (Details)
Note 5 - Intangible Assets - Schedule of Amortization of Intangible Assets (Details)
Estimated useful lives (Year)
Note 5 - Intangible Assets - Schedule of Estimated Future Amortization Expense of Intangible Assets (Details)
Note 6 - Inventories - Inventories (Details)
Note 7 - Share-based Compensation - Stock Option Activity (Details)
Note 7 - Share-based Compensation - Schedule of Share-based Compensation Expense (Details)
Note 8 - Shareholders' Equity - Stock Repurchase Program (Details)
Note 9 - Fair Value Measurements - Fair Value of Financial Instruments (Details)
clro_AmortizationReversalOfDeferredCharges
Amortization of deferred rent
Represents the amount of amortization (reversal) deferred charges.
US States and Political Subdivisions Debt Securities [Member]
Notes To Financial Statements
Software and Licenses [Member]
Information related to software and licenses.
Notes To Financial Statements [Abstract]
Equipment Sales [Member]
Information related to equipment sales.
Operating expenses:
Share-based Compensation, Stock Options, Activity [Table Text Block]
Change in foreign currency translation adjustment
Proceeds from maturities and sales of marketable securities
clro_PaymentsForRepurchaseOfStockOptions
Repurchase and cancellation of stock
The cash outflow associated with the repurchase of stock options.
Long-term marketable securities
Depreciation and amortization expense
Corporate Debt Securities [Member]
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]
Intangible Assets Disclosure [Text Block]
Long-term inventories, net
us-gaap_AssetsCurrent
Total current assets
Weighted average exercise price, options exercisable at end of March 31, 2018 (in dollars per share)
Stockholders' Equity Note Disclosure [Text Block]
Options exercisable at end of March 31, 2018 (in shares)
Common stock, par value $0.001, 50,000,000 shares authorized, 8,301,273 and 8,319,022 shares issued and outstanding
us-gaap_PaymentsToAcquireMarketableSecurities
Purchases of marketable securities
Financial Instruments [Domain]
Adjustments to reconcile net loss to net cash used in operating activities:
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Weighted average exercise price, options outstanding at beginning of year (in dollars per share)
Weighted average exercise price, options outstanding at March 31, 2018 (in dollars per share)
Common stock, shares authorized (in shares)
Americas [Member]
Weighted average exercise price, forfeited prior to vesting (in dollars per share)
Common stock, shares issued (in shares)
Deferred product revenue
Contract with Customer, Liability, Current
Weighted average exercise price, canceled or expired (in dollars per share)
Financial Instrument [Axis]
Common stock, par value (in dollars per share)
Weighted average exercise price, granted (in dollars per share)
Weighted average exercise price, exercised (in dollars per share)
Accrued liabilities
Range [Domain]
Maximum [Member]
Minimum [Member]
Accounts payable
Product and Service [Axis]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance
Options outstanding at beginning of year (in shares)
Options outstanding at March 31, 2018 (in shares)
Deferred income taxes
Product and Service [Domain]
Range [Axis]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod
Number of shares, canceled or expired (in shares)
us-gaap_PolicyTextBlockAbstract
Accounting Policies
Geographical [Axis]
Geographical [Domain]
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block]
Trade Names [Member]
Inventories, net
Other Intangible Assets [Member]
Revenue
Revenue from Contract with Customer, Including Assessed Tax
us-gaap_PaymentsToAcquireIntangibleAssets
Purchase of intangibles
Dilutive common stock equivalents using treasury stock method (in shares)
Fair Value, Inputs, Level 3 [Member]
us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Purchase of property and equipment
Weighted average options outstanding (in shares)
Fair Value Hierarchy and NAV [Domain]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized
Fair Value, Inputs, Level 1 [Member]
Fair Value, Inputs, Level 2 [Member]
Cash paid for income taxes
Fair Value Hierarchy and NAV [Axis]
Current liabilities:
us-gaap_Assets
Total assets
Plan Name [Axis]
us-gaap_IncreaseDecreaseInDeferredRevenue
Deferred product revenue
Shareholders' Equity and Share-based Payments [Text Block]
Plan Name [Domain]
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options
Cash flows from operating activities:
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition
Statement [Line Items]
Allowance for doubtful accounts
Receivables, net of allowance for doubtful accounts of $491 and $472, respectively
Patents and Technological Know-how [Member]
Represents information pertaining to Patents and Technological Know-how.
Finite-Lived Intangible Assets by Major Class [Axis]
Proprietary Software [Member]
Represents information pertaining to Proprietary Software.
Finite-Lived Intangible Assets, Major Class Name [Domain]
Marketable securities
Additional paid-in capital
Raw materials
clro_InventoryNoncurrentRawMaterialsNetOfReserves
Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items that are classified as noncurrent.
Finished goods
clro_InventoryNoncurrentFinishedGoodsNetOfReserves
Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are classified as noncurrent.
clro_DistributorChannelInventories
Distributor Channel Inventories
The carrying value of distributor channel inventories.
Schedule of Inventory Current and Noncurrent [Table Text Block]
Tabular disclosure of inventories.
Other income, net
Shareholders' equity:
Current assets:
Fair Value Disclosures [Text Block]
Net loss
Net loss
Net loss
us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
Accumulated amortization
us-gaap_FiniteLivedIntangibleAssetsNet
Total intangible assets, net
Total
Intangibles, net
us-gaap_FiniteLivedIntangibleAssetsGross
Intangible assets, gross
us-gaap_Liabilities
Total liabilities
us-gaap_NetCashProvidedByUsedInFinancingActivities
Net cash used in financing activities
us-gaap_OperatingIncomeLoss
Operating loss
us-gaap_NetCashProvidedByUsedInOperatingActivities
Net cash used in operating activities
Prepaid expenses and other assets
us-gaap_NetCashProvidedByUsedInInvestingActivities
Net cash provided by (used in) investing activities
Effect of exchange rate changes on cash and cash equivalents
us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease
Net increase (decrease) in cash and cash equivalents
us-gaap_GrossProfit
Gross profit
Cost of goods sold
Accounting Standards Update 2014-09 [Member]
Change of inventory to net realizable value
Inventory Write-down
Property and equipment, net
Type of Adoption [Domain]
Adjustments for New Accounting Pronouncements [Axis]
us-gaap_PaymentsOfDividends
Dividend payments
Cash flows from investing activities:
Income taxes payable
us-gaap_AvailableForSaleSecuritiesDebtSecurities
Total available-for-sale securities, estimated fair value
Retained Earnings [Member]
Earnings Per Share [Text Block]
Initial Application Period Cumulative Effect Transition [Axis]
Initial Application Period Cumulative Effect Transition [Domain]
Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Net proceeds from equity-based compensation programs
Share Repurchase Program [Domain]
us-gaap_StockRepurchaseProgramAuthorizedAmount1
Stock Repurchase Program, Authorized Amount
us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Loss before income taxes
us-gaap_IncreaseDecreaseInAccruedLiabilities
Accrued liabilities
Provision for (benefit from) income taxes
Class of Treasury Stock [Table Text Block]
Equity Components [Axis]
Equity Component [Domain]
Available-for-sale Securities, Debt Maturities [Table Text Block]
Tabular disclosure of maturities of available-for-sale securities.
Share Repurchase Program [Axis]
us-gaap_IncreaseDecreaseInAccountsPayable
Accounts payable
clro_CapitalizedPatentDefenseCosts
Capitalized patent defense costs
Represents payments for capitalized patent defense costs.
us-gaap_OperatingExpenses
Total operating expenses
General and administrative
Cash and cash equivalents
Cash and cash equivalents at the beginning of the period
Cash and cash equivalents at the end of the period
us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities
Other long-term liabilities
Disaggregation of Revenue [Table Text Block]
Revenue from Contract with Customer [Text Block]
Amendment Flag
General and Administrative Expense [Member]
us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate
Unrecognized Tax Benefits that Would Impact Effective Tax Rate
Accounting Policies [Abstract]
Comprehensive loss:
us-gaap_ComprehensiveIncomeNetOfTax
Comprehensive loss
New Accounting Pronouncements, Policy [Policy Text Block]
Selling and Marketing Expense [Member]
us-gaap_CommonStockDividendsPerShareDeclared
Common Stock, Dividends, Per Share, Declared
us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption
Cumulative Effect of New Accounting Principle in Period of Adoption
Unified Communications End Points [Member]
Information related to unified communications end points.
Common stock, shares outstanding (in shares)
Professional Audio Products [Member]
Information related to professional audio products.
Asia Middle East and Australia [Member]
Information related to the regions of Asia, the Middle East and Australia.
Europe and Africa [Member]
Information related to the regions of Europe and Africa.
Current Fiscal Year End Date
Video Products [Member]
Information related to video products.
Cost of Sales [Member]
us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets
Prepaid expenses and other assets
Research and Development Expense [Member]
Document Fiscal Period Focus
Document Fiscal Year Focus
Document Period End Date
Income Statement Location [Axis]
Income Statement Location [Domain]
clro_EffectiveIncomeTaxRateContinuingOperationsForecastedIncreaseDecreaseInRate
Effective Income Tax Rate, Continuing Operations, Forecasted Increase (Decrease) in Rate
Represents the increase (decrease) between the prior period effective income tax rate and the current period forecasted effective income tax rate.
Document Type
clro_EffectiveTaxRateAfterDiscreetBenefits
Effective Tax Rate After Discreet Benefits
Represents the effective tax rate after discreet benefits.
clro_EffectiveTaxRateIncludingLossJurisdictions
Effective Tax Rate, Including Loss Jurisdictions
The forecasted effective tax rate which includes loss jurisdiction for which no benefit from forecasted current year losses is anticipated.
Document Information [Line Items]
Document Information [Table]
Entity Filer Category
Entity Current Reporting Status
Entity Voluntary Filers
Entity Well-known Seasoned Issuer
us-gaap_IncreaseDecreaseInReceivables
Receivables
clro_SharebasedCompensationArrangementBySharebasedPaymentAwardNumberOfSharesAuthorizedAndUnissued
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares, Authorized and Unissued
Represents the number of shares authorized but not issued.
The 2007 Equity Incentive Plan [Member]
The equity incentive plan approved by the company in 2007.
Anti-dilutive options not included in the computations (in shares)
Diluted weighted average shares outstanding (in shares)
clro_StockRepurchaseProgramAdditionalAuthorizedAmount
Stock Repurchase Program, Additional Authorized Amount
Amount of additional stock repurchase plan authorized in a renewed and extended stock repurchase program.
Average price paid per share (in dollars per share)
Total cost of shares repurchased divided by the total number of shares repurchased.
Entity Central Index Key
Publicly Announced Stock Repurchase Program [Member]
A stock repurchase program that has been publicly announced.
Entity Registrant Name
Entity [Domain]
Legal Entity [Axis]
Statement [Table]
Scenario [Axis]
Statement of Financial Position [Abstract]
Diluted loss per common share (in dollars per share)
Diluted loss per share (in dollars per share)
Scenario, Unspecified [Domain]
Basic weighted average shares outstanding (in shares)
Amortization of intangible assets
us-gaap_EffectiveIncomeTaxRateContinuingOperations
Effective Income Tax Rate Reconciliation, Percent, Total
us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent
Basic loss per common share (in dollars per share)
Basic loss per share (in dollars per share)
Available-for-sale securities
Total number of shares purchased (in shares)
Statement of Cash Flows [Abstract]
Entity Common Stock, Shares Outstanding (in shares)
Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]
Income Statement [Abstract]
Amortized cost
us-gaap_IncreaseDecreaseInInventories
Inventories
Trading Symbol
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss
Gross unrealized holding losses
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Gross unrealized holding losses, less than 12 months
us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Gross unrealized holding losses, more than 12 months
Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block]
us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Number of shares, exercised (in shares)
us-gaap_TableTextBlock
Notes Tables
Schedule of Available-for-sale Securities Reconciliation [Table Text Block]
Estimated fair value, less than 12 months
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block]
Estimated fair value, more than 12 months
Finite-lived Intangible Assets Amortization Expense [Table Text Block]
Estimated fair value
Gross unrealized holding gains
us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Gross unrealized holding losses
Provision for (recoveries of) doubtful accounts, net
us-gaap_DividendPayableDateToBePaidDayMonthAndYear
Dividends Payable, Date to be Paid
Cash flows from financing activities:
Number of shares, granted (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod
Number of shares, forfeited prior to vesting (in shares)
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]
Other long-term liabilities
Sales and marketing
us-gaap_DividendsPayableDateOfRecordDayMonthAndYear
Dividends Payable, Date of Record
Raw materials
us-gaap_InventoryRawMaterialsNetOfReserves
us-gaap_LiabilitiesAndStockholdersEquity
Total liabilities and shareholders' equity
Finished goods
us-gaap_InventoryFinishedGoodsNetOfReserves
Retained earnings
Research and product development
Accumulated other comprehensive loss
Deferred rent
Distributor channel inventories
Retail Related Inventory, Total
Changes in operating assets and liabilities:
us-gaap_StockholdersEquity
Total shareholders' equity
us-gaap_DisclosureTextBlockAbstract
Notes to Financial Statements
Inventory Disclosure [Text Block]
Class of Stock [Axis]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
Subsequent Events [Text Block]
us-gaap_DeferredIncomeTaxExpenseBenefit
Deferred income taxes
us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
Total available-for-sale securities, amortized cost
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive
Thereafter
Due after one year through five years, amortized cost
us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear
2018 (Remainder)