3.19.1 html 166 311 1 false 60 0 false 10 false false R1.htm 100000 - Document - Document and Entity Information Document Sheet http://www.ctg.com/20190329/taxonomy/role/DocumentDocumentAndEntityInformationDocument Document and Entity Information Document Cover 1 false false R2.htm 100010 - Statement - Condensed Consolidated Statements of Income (Unaudited) Sheet http://www.ctg.com/20190329/taxonomy/role/StatementCondensedConsolidatedStatementsOfIncomeUnaudited Condensed Consolidated Statements of Income (Unaudited) Statements 2 false false R3.htm 100020 - Statement - Condensed Consolidated Statements of Comprehensive Income (Unaudited) Sheet http://www.ctg.com/20190329/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncomeUnaudited Condensed Consolidated Statements of Comprehensive Income (Unaudited) Statements 3 false false R4.htm 100030 - Statement - Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) Sheet http://www.ctg.com/20190329/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncomeUnauditedParenthetical Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) Statements 4 false false R5.htm 100040 - Statement - Condensed Consolidated Balance Sheets (Unaudited) Sheet http://www.ctg.com/20190329/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsUnaudited Condensed Consolidated Balance Sheets (Unaudited) Statements 5 false false R6.htm 100050 - Statement - Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) Sheet http://www.ctg.com/20190329/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsUnauditedParenthetical Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) Statements 6 false false R7.htm 100060 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited) Sheet http://www.ctg.com/20190329/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited Condensed Consolidated Statements of Cash Flows (Unaudited) Statements 7 false false R8.htm 100070 - Statement - Condensed Consolidated Statements of Shareholders' Equity (Unaudited) Sheet http://www.ctg.com/20190329/taxonomy/role/StatementCondensedConsolidatedStatementsOfShareholdersEquityUnaudited Condensed Consolidated Statements of Shareholders' Equity (Unaudited) Statements 8 false false R9.htm 100080 - Disclosure - Financial Statements Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureFinancialStatements Financial Statements Notes 9 false false R10.htm 100090 - Disclosure - Summary of Significant Accounting Policies Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPolicies Summary of Significant Accounting Policies Notes 10 false false R11.htm 100100 - Disclosure - Acquisitions Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAcquisitions Acquisitions Notes 11 false false R12.htm 100110 - Disclosure - Net Income Per Share Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureNetIncomePerShare Net Income Per Share Notes 12 false false R13.htm 100120 - Disclosure - Operating Leases Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureOperatingLeases Operating Leases Notes 13 false false R14.htm 100130 - Disclosure - Debt Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureDebt Debt Notes 14 false false R15.htm 100140 - Disclosure - Accumulated Other Comprehensive Loss Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLoss Accumulated Other Comprehensive Loss Notes 15 false false R16.htm 100150 - Disclosure - Income Taxes Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureIncomeTaxes Income Taxes Notes 16 false false R17.htm 100160 - Disclosure - Deferred Compensation and Other Benefits Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureDeferredCompensationAndOtherBenefits Deferred Compensation and Other Benefits Notes 17 false false R18.htm 100170 - Disclosure - Equity-based Compensation Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureEquityBasedCompensation Equity-based Compensation Notes 18 false false R19.htm 100180 - Disclosure - Treasury Stock Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureTreasuryStock Treasury Stock Notes 19 false false R20.htm 100190 - Disclosure - Significant Customers Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSignificantCustomers Significant Customers Notes 20 false false R21.htm 100200 - Disclosure - Summary of Significant Accounting Policies (Policies) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies Summary of Significant Accounting Policies (Policies) Policies http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPolicies 21 false false R22.htm 100210 - Disclosure - Summary of Significant Accounting Policies (Tables) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesTables Summary of Significant Accounting Policies (Tables) Tables http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPolicies 22 false false R23.htm 100220 - Disclosure - Acquisitions (Tables) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAcquisitionsTables Acquisitions (Tables) Tables http://www.ctg.com/20190329/taxonomy/role/DisclosureAcquisitions 23 false false R24.htm 100230 - Disclosure - Net Income Per Share (Tables) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureNetIncomePerShareTables Net Income Per Share (Tables) Tables http://www.ctg.com/20190329/taxonomy/role/DisclosureNetIncomePerShare 24 false false R25.htm 100240 - Disclosure - Operating Leases (Tables) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureOperatingLeasesTables Operating Leases (Tables) Tables http://www.ctg.com/20190329/taxonomy/role/DisclosureOperatingLeases 25 false false R26.htm 100250 - Disclosure - Accumulated Other Comprehensive Loss (Tables) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossTables Accumulated Other Comprehensive Loss (Tables) Tables http://www.ctg.com/20190329/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLoss 26 false false R27.htm 100260 - Disclosure - Deferred Compensation and Other Benefits (Tables) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureDeferredCompensationAndOtherBenefitsTables Deferred Compensation and Other Benefits (Tables) Tables http://www.ctg.com/20190329/taxonomy/role/DisclosureDeferredCompensationAndOtherBenefits 27 false false R28.htm 100270 - Disclosure - Financial Statements - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureFinancialStatementsAdditionalInformationDetails Financial Statements - Additional Information (Details) Details 28 false false R29.htm 100280 - Disclosure - Summary of Significant Accounting Policies - Basis of Presentation and Consolidation (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesBasisOfPresentationAndConsolidationDetails Summary of Significant Accounting Policies - Basis of Presentation and Consolidation (Details) Details 29 false false R30.htm 100290 - Disclosure - Summary of Significant Accounting Policies - Summary of IT Solutions and IT and Other Staffing Revenue as Percentage of Total Revenue (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesSummaryOfITSolutionsAndITAndOtherStaffingRevenueAsPercentageOfTotalRevenueDetails Summary of Significant Accounting Policies - Summary of IT Solutions and IT and Other Staffing Revenue as Percentage of Total Revenue (Details) Details 30 false false R31.htm 100300 - Disclosure - Summary of Significant Accounting Policies - Revenue by Vertical Market as Percentage of Total Revenue (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesRevenueByVerticalMarketAsPercentageOfTotalRevenueDetails Summary of Significant Accounting Policies - Revenue by Vertical Market as Percentage of Total Revenue (Details) Details 31 false false R32.htm 100310 - Disclosure - Summary of Significant Accounting Policies - Revenue by Contract Type (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesRevenueByContractTypeDetails Summary of Significant Accounting Policies - Revenue by Contract Type (Details) Details 32 false false R33.htm 100320 - Disclosure - Summary of Significant Accounting Policies - Schedule of Revenue by Geographic Location (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfRevenueByGeographicLocationDetails Summary of Significant Accounting Policies - Schedule of Revenue by Geographic Location (Details) Details 33 false false R34.htm 100330 - Disclosure - Summary of Significant Accounting Policies - Transaction Price Allocated to Remaining Performance Obligations (Details 1) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesTransactionPriceAllocatedToRemainingPerformanceObligationsDetails1 Summary of Significant Accounting Policies - Transaction Price Allocated to Remaining Performance Obligations (Details 1) Details 34 false false R35.htm 100340 - Disclosure - Summary of Significant Accounting Policies - Transaction Price Allocated to Remaining Performance Obligations (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesTransactionPriceAllocatedToRemainingPerformanceObligationsDetails Summary of Significant Accounting Policies - Transaction Price Allocated to Remaining Performance Obligations (Details) Details 35 false false R36.htm 100350 - Disclosure - Summary of Significant Accounting Policies - Fair Value (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesFairValueDetails Summary of Significant Accounting Policies - Fair Value (Details) Details 36 false false R37.htm 100360 - Disclosure - Summary of Significant Accounting Policies - Life Insurance Policies (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesLifeInsurancePoliciesDetails Summary of Significant Accounting Policies - Life Insurance Policies (Details) Details 37 false false R38.htm 100370 - Disclosure - Summary of Significant Accounting Policies - Schedule of Property, Equipment and Capitalized Software (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfPropertyEquipmentAndCapitalizedSoftwareDetails Summary of Significant Accounting Policies - Schedule of Property, Equipment and Capitalized Software (Details) Details 38 false false R39.htm 100380 - Disclosure - Summary of Significant Accounting Policies - Property, Equipment and Capitalized Software Costs - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesPropertyEquipmentAndCapitalizedSoftwareCostsAdditionalInformationDetails Summary of Significant Accounting Policies - Property, Equipment and Capitalized Software Costs - Additional Information (Details) Details 39 false false R40.htm 100390 - Disclosure - Summary of Significant Accounting Policies - Guarantees (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesGuaranteesDetails Summary of Significant Accounting Policies - Guarantees (Details) Details 40 false false R41.htm 100400 - Disclosure - Summary of Significant Accounting Policies - Summary of Changes in Carrying Amount of Goodwill (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesSummaryOfChangesInCarryingAmountOfGoodwillDetails Summary of Significant Accounting Policies - Summary of Changes in Carrying Amount of Goodwill (Details) Details 41 false false R42.htm 100410 - Disclosure - Summary of Significant Accounting Policies - Summary of Acquired Intangible Assets (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesSummaryOfAcquiredIntangibleAssetsDetails Summary of Significant Accounting Policies - Summary of Acquired Intangible Assets (Details) Details 42 false false R43.htm 100420 - Disclosure - Summary of Significant Accounting Policies - Summary of Estimated Amortization Expense (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesSummaryOfEstimatedAmortizationExpenseDetails Summary of Significant Accounting Policies - Summary of Estimated Amortization Expense (Details) Details 43 false false R44.htm 100430 - Disclosure - Summary of Significant Accounting Policies - Recent Issued Accounting Standards (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesRecentIssuedAccountingStandardsDetails Summary of Significant Accounting Policies - Recent Issued Accounting Standards (Details) Details 44 false false R45.htm 100440 - Disclosure - Acquisitions - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetails Acquisitions - Additional Information (Details) Details 45 false false R46.htm 100450 - Disclosure - Acquisitions - Summary of Acquisition Date Fair Value of Consideration (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAcquisitionsSummaryOfAcquisitionDateFairValueOfConsiderationDetails Acquisitions - Summary of Acquisition Date Fair Value of Consideration (Details) Details 46 false false R47.htm 100460 - Disclosure - Acquisitions - Summary of Allocation of Aggregate Purchase Consideration to Fair Values of Assets Acquired and Liabilities Assumed (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAcquisitionsSummaryOfAllocationOfAggregatePurchaseConsiderationToFairValuesOfAssetsAcquiredAndLiabilitiesAssumedDetails Acquisitions - Summary of Allocation of Aggregate Purchase Consideration to Fair Values of Assets Acquired and Liabilities Assumed (Details) Details 47 false false R48.htm 100470 - Disclosure - Acquisitions - Summary of Intangible Assets Acquired (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAcquisitionsSummaryOfIntangibleAssetsAcquiredDetails Acquisitions - Summary of Intangible Assets Acquired (Details) Details 48 false false R49.htm 100480 - Disclosure - Net Income Per Share - Schedule of Basic and Diluted Earnings Per Share (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureNetIncomePerShareScheduleOfBasicAndDilutedEarningsPerShareDetails Net Income Per Share - Schedule of Basic and Diluted Earnings Per Share (Details) Details 49 false false R50.htm 100490 - Disclosure - Net Income Per Share - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureNetIncomePerShareAdditionalInformationDetails Net Income Per Share - Additional Information (Details) Details 50 false false R51.htm 100500 - Disclosure - Operating Leases - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureOperatingLeasesAdditionalInformationDetails Operating Leases - Additional Information (Details) Details 51 false false R52.htm 100510 - Disclosure - Operating Leases - Summary of Maturities of Lease Liabilities for Operating Liabilities (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureOperatingLeasesSummaryOfMaturitiesOfLeaseLiabilitiesForOperatingLiabilitiesDetails Operating Leases - Summary of Maturities of Lease Liabilities for Operating Liabilities (Details) Details 52 false false R53.htm 100530 - Disclosure - Operating Lease - Summary of Weighted Average Remaining Lease Term, Discount Rate and Supplemental Cash Flow Information for All Operating Leases (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureOperatingLeaseSummaryOfWeightedAverageRemainingLeaseTermDiscountRateAndSupplementalCashFlowInformationForAllOperatingLeasesDetails Operating Lease - Summary of Weighted Average Remaining Lease Term, Discount Rate and Supplemental Cash Flow Information for All Operating Leases (Details) Details 53 false false R54.htm 100540 - Disclosure - Debt - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureDebtAdditionalInformationDetails Debt - Additional Information (Details) Details 54 false false R55.htm 100550 - Disclosure - Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossScheduleOfAccumulatedOtherComprehensiveLossDetails Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Details) Details 55 false false R56.htm 100560 - Disclosure - Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Parenthetical) (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossScheduleOfAccumulatedOtherComprehensiveLossParentheticalDetails Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Parenthetical) (Details) Details 56 false false R57.htm 100570 - Disclosure - Accumulated Other Comprehensive Loss - Schedule of Net Benefit Costs (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossScheduleOfNetBenefitCostsDetails Accumulated Other Comprehensive Loss - Schedule of Net Benefit Costs (Details) Details 57 false false R58.htm 100580 - Disclosure - Income Taxes - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureIncomeTaxesAdditionalInformationDetails Income Taxes - Additional Information (Details) Details 58 false false R59.htm 100590 - Disclosure - Deferred Compensation and Other Benefits - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureDeferredCompensationAndOtherBenefitsAdditionalInformationDetails Deferred Compensation and Other Benefits - Additional Information (Details) Details 59 false false R60.htm 100600 - Disclosure - Deferred Compensation and Other Benefits - Schedule of Net Periodic Pension Cost (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureDeferredCompensationAndOtherBenefitsScheduleOfNetPeriodicPensionCostDetails Deferred Compensation and Other Benefits - Schedule of Net Periodic Pension Cost (Details) Details 60 false false R61.htm 100610 - Disclosure - Deferred Compensation and Other Benefits - Schedule of Change in Fair Value of Plan Assets for NDBP (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureDeferredCompensationAndOtherBenefitsScheduleOfChangeInFairValueOfPlanAssetsForNDBPDetails Deferred Compensation and Other Benefits - Schedule of Change in Fair Value of Plan Assets for NDBP (Details) Details 61 false false R62.htm 100620 - Disclosure - Equity-based Compensation - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureEquityBasedCompensationAdditionalInformationDetails Equity-based Compensation - Additional Information (Details) Details 62 false false R63.htm 100630 - Disclosure - Treasury Stock - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureTreasuryStockAdditionalInformationDetails Treasury Stock - Additional Information (Details) Details 63 false false R64.htm 100640 - Disclosure - Significant Customers - Additional Information (Details) Sheet http://www.ctg.com/20190329/taxonomy/role/DisclosureSignificantCustomersAdditionalInformationDetails Significant Customers - Additional Information (Details) Details 64 false false All Reports Book All Reports ctg-10q_20190329.htm ctg-20190329.xsd ctg-20190329_cal.xml ctg-20190329_def.xml ctg-20190329_lab.xml ctg-20190329_pre.xml ctg-ex31a_7.htm ctg-ex31b_6.htm ctg-ex32_8.htm http://fasb.org/us-gaap/2018-01-31 http://xbrl.sec.gov/dei/2018-01-31 http://fasb.org/srt/2018-01-31 true true