| **Fair Value Measurements (Fair Value Measurements) (Details) (USD $)In Thousands, unless otherwise specified** | 0 Months Ended                                                                                                                                                              |                                                                                                                                                                                                                           |                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | $ 893us-gaap_TradingSecurities                                                                                                                                                                                            | $ 1,024us-gaap_TradingSecurities                                                                                                                                                              |
| Mutual fund investments - equities [Member]                                                                     |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 437us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsEquitiesMember                                                                                                                  | 593us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsEquitiesMember                                                                                      |
| Mutual fund investments - bonds [Member]                                                                        |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 442us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsBondsMember                                                                                                                     | 400us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsBondsMember                                                                                         |
| Cash and equivalents [Member]                                                                                   |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 14us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= us-gaap_CashAndCashEquivalentsMember                                                                                                                      | 31us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= us-gaap_CashAndCashEquivalentsMember                                                                                          |
| Level 1 [Member]                                                                                                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 893us-gaap_TradingSecurities/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member                                                                                                         | 1,024us-gaap_TradingSecurities/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member                                                                           |
| Level 1 [Member] | Mutual fund investments - equities [Member]                                                  |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 437us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsEquitiesMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member                             | 593us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsEquitiesMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member |
| Level 1 [Member] | Mutual fund investments - bonds [Member]                                                     |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 442us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsBondsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member                                | 400us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsBondsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member    |
| Level 1 [Member] | Cash and equivalents [Member]                                                                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 14us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= us-gaap_CashAndCashEquivalentsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member                                 | 31us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= us-gaap_CashAndCashEquivalentsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member     |
| Level 2 [Member]                                                                                                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 0us-gaap_TradingSecurities/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member                                                                                                           | 0us-gaap_TradingSecurities/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member                                                                               |
| Level 2 [Member] | Mutual fund investments - equities [Member]                                                  |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsEquitiesMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member                               | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsEquitiesMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member   |
| Level 2 [Member] | Mutual fund investments - bonds [Member]                                                     |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsBondsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member                                  | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsBondsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member      |
| Level 2 [Member] | Cash and equivalents [Member]                                                                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= us-gaap_CashAndCashEquivalentsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member                                  | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= us-gaap_CashAndCashEquivalentsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member      |
| Level 3 [Member]                                                                                                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 0us-gaap_TradingSecurities/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member                                                                                                           | 0us-gaap_TradingSecurities/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member                                                                               |
| Level 3 [Member] | Mutual fund investments - equities [Member]                                                  |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsEquitiesMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member                               | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsEquitiesMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member   |
| Level 3 [Member] | Mutual fund investments - bonds [Member]                                                     |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsBondsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member                                  | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= clc_MutualFundInvestmentsBondsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member      |
| Level 3 [Member] | Cash and equivalents [Member]                                                                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Restricted trust, included in Other noncurrent assets                                                           |                                                                                                                                                                        | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= us-gaap_CashAndCashEquivalentsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member                                  | 0us-gaap_TradingSecurities/ us-gaap_FairValueByAssetClassAxis= us-gaap_CashAndCashEquivalentsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member      |
| TransWeb [Member]                                                                                               |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Foreign exchange contracts, included in Prepaid expenses and other current assets                               |                                                                                                                                                                        | 0us-gaap_OtherLiabilitiesFairValueDisclosure/ us-gaap_BusinessAcquisitionAxis= clc_TranswebMember                                                                                                                         | 0us-gaap_OtherLiabilitiesFairValueDisclosure/ us-gaap_BusinessAcquisitionAxis= clc_TranswebMember                                                                                             |
| Fair value of earn-out payment                                                                                  | 1,018us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings/ us-gaap_BusinessAcquisitionAxis= clc_TranswebMember |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Prepaid Expenses and Other Current Assets [Member]                                                              |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Foreign exchange contracts, included in Prepaid expenses and other current assets                               |                                                                                                                                                                        | 362us-gaap_OtherLiabilitiesFairValueDisclosure/ us-gaap_BalanceSheetLocationAxis= us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember                                                                                      |                                                                                                                                                                                          |
| Prepaid Expenses and Other Current Assets [Member] | Level 1 [Member]                                           |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Foreign exchange contracts, included in Prepaid expenses and other current assets                               |                                                                                                                                                                        | 0us-gaap_OtherLiabilitiesFairValueDisclosure/ us-gaap_BalanceSheetLocationAxis= us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel1Member   |                                                                                                                                                                                          |
| Prepaid Expenses and Other Current Assets [Member] | Level 2 [Member]                                           |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Foreign exchange contracts, included in Prepaid expenses and other current assets                               |                                                                                                                                                                        | 362us-gaap_OtherLiabilitiesFairValueDisclosure/ us-gaap_BalanceSheetLocationAxis= us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member |                                                                                                                                                                                          |
| Prepaid Expenses and Other Current Assets [Member] | Level 3 [Member]                                           |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Foreign exchange contracts, included in Prepaid expenses and other current assets                               |                                                                                                                                                                        | 0us-gaap_OtherLiabilitiesFairValueDisclosure/ us-gaap_BalanceSheetLocationAxis= us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel3Member   |                                                                                                                                                                                          |
| Accrued Liabilities [Member]                                                                                    |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Foreign exchange contracts, included in Prepaid expenses and other current assets                               |                                                                                                                                                                        | 367us-gaap_OtherLiabilitiesFairValueDisclosure/ us-gaap_BalanceSheetLocationAxis= us-gaap_AccruedLiabilitiesMember                                                                                                        |                                                                                                                                                                                          |
| Accrued Liabilities [Member] | Level 2 [Member]                                                                 |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                |                                                                                                                                                                        |                                                                                                                                                                                                                      |                                                                                                                                                                                          |
| Foreign exchange contracts, included in Prepaid expenses and other current assets                               |                                                                                                                                                                        | $ 367us-gaap_OtherLiabilitiesFairValueDisclosure/ us-gaap_BalanceSheetLocationAxis= us-gaap_AccruedLiabilitiesMember/ us-gaap_FairValueByFairValueHierarchyLevelAxis= us-gaap_FairValueInputsLevel2Member                 |                                                                                                                                                                                          |

| X                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability 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)(1) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258
+ Details**Name:**us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value portion of other liabilities.
+ References
No definition available.
+ Details**Name:**us-gaap_OtherLiabilitiesFairValueDisclosure**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878
+ Details**Name:**us-gaap_TradingSecurities**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_BalanceSheetLocationAxis=us-gaap_AccruedLiabilitiesMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_BalanceSheetLocationAxis=us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_BusinessAcquisitionAxis=clc_TranswebMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                              |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_FairValueByAssetClassAxis=clc_MutualFundInvestmentsBondsMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_FairValueByAssetClassAxis=clc_MutualFundInvestmentsEquitiesMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                              |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_FairValueByAssetClassAxis=us-gaap_CashAndCashEquivalentsMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |