XML 25 R57.htm IDEA: XBRL DOCUMENT v2.4.1.9
Retirement Benefit Plans Part 1 (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]      
Total cost of benefit for U.S. and Non-U.S. Plans $ 11,334us-gaap_PensionAndOtherPostretirementBenefitExpense $ 11,766us-gaap_PensionAndOtherPostretirementBenefitExpense $ 11,192us-gaap_PensionAndOtherPostretirementBenefitExpense
Maximum employer contribution to 401(k) Plan as a percentage of employee's compensation 3.00%us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent    
Minimum service period required to be eligible for profit sharing contribution to 401(k) plan (in years) 1    
Expenses for 401(k) Plan 7,475us-gaap_DefinedContributionPlanCostRecognized 6,423us-gaap_DefinedContributionPlanCostRecognized 6,226us-gaap_DefinedContributionPlanCostRecognized
U.K. Pension Plan      
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]      
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Purchases, sales, issuances and settlements, net (96)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements
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Net gain 974tnc_Fairvalueassetswithunobservableinputsreconciliationgainsandlosses
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U.S. and U.K. Pension Plans | Fair Value      
Fair Value of Plan Assets by Investment Type      
Fair value of plan assets 61,893us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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U.S. and U.K. Pension Plans | Level 1      
Fair Value of Plan Assets by Investment Type      
Fair value of plan assets 51,904us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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U.S. and U.K. Pension Plans | Level 2      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Level 3      
Fair Value of Plan Assets by Investment Type      
Fair value of plan assets 9,989us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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U.S. and U.K. Pension Plans | Cash and Cash Equivalents | Fair Value      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Cash and Cash Equivalents | Level 1      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Cash and Cash Equivalents | Level 2      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Cash and Cash Equivalents | Level 3      
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U.S. and U.K. Pension Plans | Mutual Funds - U.S. Large-Cap | Fair Value      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Mutual Funds - U.S. Large-Cap | Level 1      
Fair Value of Plan Assets by Investment Type      
Fair value of plan assets 12,955us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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U.S. and U.K. Pension Plans | Mutual Funds - U.S. Large-Cap | Level 2      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Mutual Funds - U.S. Large-Cap | Level 3      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Mutual Funds - U.S. Small-Cap | Fair Value      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Mutual Funds - U.S. Small-Cap | Level 1      
Fair Value of Plan Assets by Investment Type      
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U.S. and U.K. Pension Plans | Mutual Funds - U.S. Small-Cap | Level 2      
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U.S. and U.K. Pension Plans | Mutual Funds - U.S. Small-Cap | Level 3      
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U.S. and U.K. Pension Plans | Mutual Funds - International Equities | Fair Value      
Fair Value of Plan Assets by Investment Type      
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Fair Value of Plan Assets by Investment Type      
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Fair Value of Plan Assets by Investment Type      
Fair value of plan assets 9,989us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= tnc_InvestmentAccountHeldByPensionPlanMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= tnc_USAndUKPensionPlansMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_EstimateOfFairValueFairValueDisclosureMember
[1] 9,733us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= tnc_InvestmentAccountHeldByPensionPlanMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= tnc_USAndUKPensionPlansMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_EstimateOfFairValueFairValueDisclosureMember
[1]  
U.S. and U.K. Pension Plans | Investment Account Held By Pension Plan | Level 1      
Fair Value of Plan Assets by Investment Type      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= tnc_InvestmentAccountHeldByPensionPlanMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= tnc_USAndUKPensionPlansMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
[1] 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= tnc_InvestmentAccountHeldByPensionPlanMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= tnc_USAndUKPensionPlansMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
[1]  
U.S. and U.K. Pension Plans | Investment Account Held By Pension Plan | Level 2      
Fair Value of Plan Assets by Investment Type      
Fair value of plan assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= tnc_InvestmentAccountHeldByPensionPlanMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= tnc_USAndUKPensionPlansMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
[1] 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= tnc_InvestmentAccountHeldByPensionPlanMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= tnc_USAndUKPensionPlansMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
[1]  
U.S. and U.K. Pension Plans | Investment Account Held By Pension Plan | Level 3      
Fair Value of Plan Assets by Investment Type      
Fair value of plan assets $ 9,989us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= tnc_InvestmentAccountHeldByPensionPlanMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= tnc_USAndUKPensionPlansMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
[1] $ 9,733us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= tnc_InvestmentAccountHeldByPensionPlanMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= tnc_USAndUKPensionPlansMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
[1]  
[1] This category is comprised of investments in insurance contracts.