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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Additional payments deferred on the acquisition date9false 4cdns_RelatedPartyOwnershipPercentageInAcquiredCompanycdns_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7truetruefalse0.0850.085falsefalsefalse8falsetruefalse00falsefalsefalsenum:percentItemTypepureRelated Party, Ownership Percentage in Acquired CompanyNo definition available.false0Related party, ownership percentage in acquired company10false 4us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLifeus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse008 yearsfalsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalsexbrli:durationItemTypenaWeighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16265-109275 false0Acquired definite-lived intangible assets, weighted average useful life11false 4us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmountus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse96000009.6falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse96000009.6falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141 -Paragraph 52 -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Goodwill, expected tax deductible amount12false 4us-gaap_BusinessCombinationAcquisitionRelatedCostsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse48000004.8USD$falsetruefalse2truefalsefalse11000001.1USD$falsetruefalse3truefalsefalse82000008.2USD$falsetruefalse4truefalsefalse11000001.1USD$falsetruefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. 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