Basis of Reporting (Details Textual) (USD $)	3 Months Ended
Apr. 04, 2015	Mar. 29, 2014	Jan. 03, 2015
Accounting Policies [Line Items]
Implementation Costs	$ 97,000crtn_ImplementationCosts	$ 150,000crtn_ImplementationCosts
Research and Development Expense, Software (Excluding Acquired in Process Cost)	208,000	204,000
Foreign currency translation adjustment	5,300,000		4,600,000
Foreign Currency Transaction Gain (Loss), before Tax	(168,000)	58,000
Inventory, Net	3,000,000us-gaap_InventoryNet		3,000,000us-gaap_InventoryNet
Capitalized Computer Software, Gross	177,000
Trade Receivables, Third Party	$ 5,800,000crtn_TradeReceivablesThirdParty		$ 6,400,000crtn_TradeReceivablesThirdParty
Stock Compensation Plan [Member]
Accounting Policies [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	207,389	58,851

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Implementation costs associated with managed service arrangements that have been deferred. Costs generally amortized over the period that the related ongoing services revenue is recognized.

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Amount of trade receivables sold to third-party financial institution.

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Research and development expense during the period related to the costs of developing and achieving technological feasibility of a computer software product to be sold, leased, or otherwise marketed.

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