CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Apr. 04, 2015	Mar. 29, 2014
Revenues	$ 18,050us-gaap_Revenues	$ 16,237us-gaap_Revenues
Cost of services	11,372us-gaap_CostOfRevenue	10,310us-gaap_CostOfRevenue
Gross Profit	6,678us-gaap_GrossProfit	5,927us-gaap_GrossProfit
Selling, general and administrative expenses (includes non-cash share-based compensation expense of $301 and $174, respectively)	7,306	5,919
(Loss) income from operations	(628)us-gaap_OperatingIncomeLoss	8us-gaap_OperatingIncomeLoss
Other expense:
Interest expense, net	(60)us-gaap_InterestIncomeExpenseNet	(8)us-gaap_InterestIncomeExpenseNet
Discount on note payable and transaction costs	0	(1,528)
Incentive warrants expense	(38)crtn_IncentiveWarrantsExpense	0crtn_IncentiveWarrantsExpense
Change in fair value of warrants and derivative liabilities	(125)	(17)
Total other expense	(223)us-gaap_NonoperatingIncomeExpense	(1,553)us-gaap_NonoperatingIncomeExpense
Loss before income taxes	(851)	(1,545)
Income tax provision	(170)us-gaap_IncomeTaxExpenseBenefit	(29)us-gaap_IncomeTaxExpenseBenefit
Net loss	(1,021)us-gaap_NetIncomeLoss	(1,574)us-gaap_NetIncomeLoss
Other comprehensive (loss) income:
Foreign currency translation adjustment	(681)	137
Comprehensive loss	$ (1,702)us-gaap_ComprehensiveIncomeNetOfTax	$ (1,437)us-gaap_ComprehensiveIncomeNetOfTax
Net loss per common share
Basic and diluted (in dollars per share)	$ (0.13)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.22)us-gaap_EarningsPerShareBasicAndDiluted
Weighted average shares used in calculation of net loss per basic and diluted common share (in shares)	8,090	7,312

Change in fair value of warrants and derivatives liabilities.

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Discount on note payable and debt issuance costs.

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Expense associated with incentive warrants earned by a strategic alliance partner.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The net amount of operating interest income (expense).

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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The net result for the period of deducting operating expenses from operating revenues.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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