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Retirement Benefit Plans Part 1 (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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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 | $ 11,334 us-gaap_PensionAndOtherPostretirementBenefitExpense |  | $ 11,766 us-gaap_PensionAndOtherPostretirementBenefitExpense |  | $ 11,192 us-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 | 7,475 us-gaap_DefinedContributionPlanCostRecognized |  | 6,423 us-gaap_DefinedContributionPlanCostRecognized |  | 6,226 us-gaap_DefinedContributionPlanCostRecognized
U.K. Pension Plan |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |
Fair value at beginning of year | 9,733 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  | 8,855 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  |
Purchases, sales, issuances and settlements, net | (96)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  | 74 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  |
Net gain | 974 tnc_Fairvalueassetswithunobservableinputsreconciliationgainsandlosses / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  | 601 tnc_Fairvalueassetswithunobservableinputsreconciliationgainsandlosses / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  |
Foreign currency | (622)tnc_Fairvalueassetswithunobservableinputsreconciliationforeigncurrencyeffects / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  | 203 tnc_Fairvalueassetswithunobservableinputsreconciliationforeigncurrencyeffects / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  |
Fair value at end of year | 9,989 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  | 9,733 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_UKPensionPlanMember |  |
U.S. and U.K. Pension Plans | Fair Value |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 61,893 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  | 62,130 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  |
U.S. and U.K. Pension Plans | Level 1 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 51,904 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  | 52,397 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |
U.S. and U.K. Pension Plans | Level 2 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |
U.S. and U.K. Pension Plans | Level 3 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 9,989 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  | 9,733 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |
U.S. and U.K. Pension Plans | Cash and Cash Equivalents | Fair Value |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 505 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  | 746 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  |
U.S. and U.K. Pension Plans | Cash and Cash Equivalents | Level 1 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 505 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  | 746 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |
U.S. and U.K. Pension Plans | Cash and Cash Equivalents | Level 2 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |
U.S. and U.K. Pension Plans | Cash and Cash Equivalents | Level 3 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - U.S. Large-Cap | Fair Value |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 12,955 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsUSLargeCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  | 20,597 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsUSLargeCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  |
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 | 12,955 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsUSLargeCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  | 20,597 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsUSLargeCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - U.S. Large-Cap | Level 2 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsUSLargeCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsUSLargeCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - U.S. Large-Cap | Level 3 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsUSLargeCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsUSLargeCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - U.S. Small-Cap | Fair Value |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 4,004 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsU.S.SmallCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  | 6,971 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsU.S.SmallCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  |
U.S. and U.K. Pension Plans | Mutual Funds - U.S. Small-Cap | Level 1 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 4,004 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsU.S.SmallCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  | 6,971 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsU.S.SmallCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - U.S. Small-Cap | Level 2 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsU.S.SmallCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsU.S.SmallCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - U.S. Small-Cap | Level 3 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsU.S.SmallCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsU.S.SmallCapMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - International Equities | Fair Value |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 3,788 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsInternationalEquitiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  | 6,328 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsInternationalEquitiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  |
U.S. and U.K. Pension Plans | Mutual Funds - International Equities | Level 1 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 3,788 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsInternationalEquitiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  | 6,328 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsInternationalEquitiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - International Equities | Level 2 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsInternationalEquitiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsInternationalEquitiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - International Equities | Level 3 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsInternationalEquitiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsInternationalEquitiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - Fixed-Income Domestic | Fair Value |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 30,652 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsFixedIncomeDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  | 17,755 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsFixedIncomeDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember |  |
U.S. and U.K. Pension Plans | Mutual Funds - Fixed-Income Domestic | Level 1 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 30,652 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsFixedIncomeDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  | 17,755 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsFixedIncomeDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - Fixed-Income Domestic | Level 2 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsFixedIncomeDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsFixedIncomeDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |
U.S. and U.K. Pension Plans | Mutual Funds - Fixed-Income Domestic | Level 3 |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsFixedIncomeDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_MutualFundsFixedIncomeDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |
U.S. and U.K. Pension Plans | Investment Account Held By Pension Plan | Fair Value |  |  |  |  |
Fair Value of Plan Assets by Investment Type |  |  |  |  |
Fair value of plan assets | 9,989 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_InvestmentAccountHeldByPensionPlanMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember | [1] | 9,733 us-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 | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_InvestmentAccountHeldByPensionPlanMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | [1] | 0 us-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 | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_InvestmentAccountHeldByPensionPlanMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | [1] | 0 us-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 | $ 9,989 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = tnc_InvestmentAccountHeldByPensionPlanMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = tnc_USAndUKPensionPlansMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | [1] | $ 9,733 us-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.

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- Definition Fair value assets with unobservable inputs reconciliation foreign currency effects + References No definition available. + Details
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- Definition Fair value assets with unobservable inputs reconciliation gains and losses + References No definition available. + Details
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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph c -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition The amount of pension and other (such as medical, dental and life insurance) postretirement benefit costs recognized during the period for (1) defined benefit plans (periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss) on assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments) and for (2) defined contribution plans (to the extent that a plan's defined contributions to an individual's account are to be made for periods in which that individual renders services, the net cost for a period is the contribution called for in that period; if a plan calls for contributions for periods after an individual retires or terminates, the estimated cost is accrued during the employee's service period). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.4) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
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