XML 81 R57.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Deferred Compensation and Retirement Plans - Additional Information (Detail) | 12 Months Ended |  |
--- | --- | --- | ---
Apr. 30, 2017 USD ($) Person | Apr. 30, 2016 USD ($) Person | Apr. 30, 2015 USD ($) | Dec. 01, 2015 Person | Apr. 30, 2014 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Recognized investment income(expense) | $ 10,842,000 | $ (3,333,000) | $ 8,829,000 |  |
Increase in market value of the underlying COLI investments | 4,918,000 | 3,984,000 | 10,509,000 |  |
Net CSV | 113,067,000 | 107,296,000 |  |  |
Long Term Performance Unit Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Value per unit award | 50,000 |  |  |  |
Annual Benefit Payments per vested unit after anniversary period | $ 25,000 |  |  |  |
Number of payments after the seventh anniversary of the grant date | 5 years |  |  |  |
Vesting percentage on each anniversary date | 25.00% |  |  |  |
CSV of COLI Contracts |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Gross CSV | $ 180,300,000 | 175,700,000 |  |  |
Outstanding policy loans | 67,200,000 | 68,400,000 |  |  |
Total death benefits payable, net of loans | 220,600,000 | 216,700,000 |  |  |
Increase in market value of the underlying COLI investments | $ 4,900,000 | 4,000,000 | 10,500,000 |  |
Equity Securities |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Target allocation range, minimum | 50.00% |  |  |  |
Target allocation range, maximum | 70.00% |  |  |  |
Debt Securities |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Target allocation range, minimum | 30.00% |  |  |  |
Target allocation range, maximum | 50.00% |  |  |  |
Other Assets |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Target allocation range, minimum | 0.00% |  |  |  |
Target allocation range, maximum | 10.00% |  |  |  |
Enhanced Wealth Accumulation Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Participant contribution period towards deferred compensation plans (in years) | 8 years |  |  |  |
Participant after tax contribution period towards deferred compensation plans (in years) | 15 years |  |  |  |
Additional deferred units to acquire (in years) | 5 years |  |  |  |
Senior Executive Incentive Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Participant contribution period towards deferred compensation plans (in years) | 4 years |  |  |  |
Participant after tax contribution period towards deferred compensation plans (in years) | 15 years |  |  |  |
Pension Plans, Defined Benefit |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Participant employment term, maximum years | 20 years |  |  |  |
Deferred Compensation Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Deferred compensation and pension plans in periodic benefit expense cost expected to be recognized | $ 2,300,000 |  |  |  |
Total benefit obligation | 121,042,000 | 124,566,000 | 89,138,000 |  | $ 86,577,000
Deferred Compensation Plan | CSV of COLI Contracts |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Gross CSV | 180,300,000 | 175,700,000 | 172,300,000 |  |
Outstanding policy loans | $ 67,200,000 | 68,400,000 | 69,600,000 |  |
Medical and Life Insurance | Legacy Hay |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Benefit plan, number of participants | Person |  |  |  | 190 |
Defined benefit plan health care cost trend rate assumed | 7.00% |  |  |  |
Defined benefit plan ultimate health care cost trend rate | 5.00% |  |  |  |
Defined benefit plan year that rate reaches ultimate trend rate | 2022 |  |  |  |
Defined benefit plan effect of one percentage point increase on accumulated postretirement benefit obligation | $ 100,000 |  |  |  |
Defined benefit plan effect of one percentage point decrease on accumulated postretirement benefit obligation | 100,000 |  |  |  |
Total benefit obligation | 12,147,000 | 13,006,000 |  |  |
International Retirement Plans |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Total benefit obligation | $ 12,000,000 | $ 15,400,000 |  |  |
Long-term benefit obligation accrued, number of participants | Person | 1,710 | 1,450 |  |  |
Company's contributions | $ 9,300,000 | $ 5,100,000 |  |  |
Executive Capital Accumulation Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Total benefit obligation | 111,584,000 | 105,676,000 | 99,461,000 |  |
Company's contributions | 6,200,000 | 23,200,000 | 19,100,000 |  |
Gain (loss) on deferred compensation plan | 10,565,000 | (1,654,000) | $ 5,900,000 |  |
Company's contributions, unamortized portion | $ 25,500,000 | 33,200,000 |  |  |
Executive Capital Accumulation Plan | Minimum |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Deferred compensation arrangement vesting period | 4 years |  |  |  |
Executive Capital Accumulation Plan | Maximum |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Deferred compensation arrangement vesting period | 5 years |  |  |  |
Defined Contribution Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Company's matching contributions | $ 1,800,000 | $ 1,700,000 |  |  |
Percentage contribution by the participants to defined contribution plan | 50.00% |  |  |  |
Company Owned Life Insurance Held In Trust | CSV of COLI Contracts |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Net CSV | $ 59,500,000 |  |  |  |
Total death benefits, net of loans held in trust | $ 99,900,000 |  |  |  |

X
- Definition Benefit Obligation Accrued Number Of Participants + References No definition available. + Details
Name: | kfy_BenefitObligationAccruedNumberOfParticipants
Namespace Prefix: | kfy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Cash Surrender Value of Life Insurance Gross + References No definition available. + Details
Name: | kfy_CashSurrenderValueOfLifeInsuranceGross
Namespace Prefix: | kfy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Death Benefits Payable Net Of Loans + References No definition available. + Details
Name: | kfy_DeathBenefitsPayableNetOfLoans
Namespace Prefix: | kfy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Death Benefits Payable Net Of Loans Held In Trust + References No definition available. + Details
Name: | kfy_DeathBenefitsPayableNetOfLoansHeldInTrust
Namespace Prefix: | kfy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The compensation expense or income recognized during the period pertaining to the deferred compensation arrangement. + References No definition available. + Details
Name: | kfy_DeferredCompensationArrangementWithIndividualCompensationExpenseIncome
Namespace Prefix: | kfy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of Company contributions that is unamortized but will be expensed in future period once the conditions are met. + References No definition available. + Details
Name: | kfy_DeferredCompensationArrangementWithIndividualEmployerContributionUnamortizedPortion
Namespace Prefix: | kfy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Defined benefit plan number of plan participants. + References No definition available. + Details
Name: | kfy_DefinedBenefitPlanNumberOfPlanParticipants
Namespace Prefix: | kfy_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of years the participant will receive payments from the plan once the participant meets the requirements under the plan. + References No definition available. + Details
Name: | kfy_ParticipantAfterTaxContributionPeriodTowardsDeferredCompensationPlans
Namespace Prefix: | kfy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of years that the participant is required to contribute into the plan. + References No definition available. + Details
Name: | kfy_ParticipantContributionPeriodTowardsDeferredCompensationPlans
Namespace Prefix: | kfy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The maximum number of years that can be used to calculate the benefits earned under the pension plan. + References No definition available. + Details
Name: | kfy_ParticipantEmploymentTerm
Namespace Prefix: | kfy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of years that the participants were able to acquire additional "deferral units" under the plan. + References No definition available. + Details
Name: | kfy_PeriodToAcquireAdditionalDeferredUnits
Namespace Prefix: | kfy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Policy Loans Payable + References No definition available. + Details
Name: | kfy_PolicyLoansPayable
Namespace Prefix: | kfy_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The annual payments that will be made for five years commencing on the seventh anniversary of the grant date. + References No definition available. + Details
Name: | kfy_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionValue
Namespace Prefix: | kfy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The number of years that the participant will obtain the annual benefit of $25,000 commencing on the seventh anniversary of the grant date. + References No definition available. + Details
Name: | kfy_ShareBasedCompensationArrangementByShareBasedPaymentAwardPaymentsAfterAnniversaryPeriod
Namespace Prefix: | kfy_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The base value per unit that will be used to determine payment that would be made upon early termination for a partially vested unit award. + References No definition available. + Details
Name: | kfy_ShareBasedCompensationArrangementByShareBasedPaymentAwardValuePerUnit
Namespace Prefix: | kfy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 4 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765 + Details
Name: | us-gaap_CashSurrenderValueOfLifeInsurance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement. + References No definition available. + Details
Name: | us-gaap_DeferredCompensationArrangementWithIndividualEmployerContribution
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6409961&loc=d3e20487-108367 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_DeferredCompensationArrangementWithIndividualRequisiteServicePeriod1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount included in accumulated other comprehensive income (AOCI) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position, including gain (loss), prior service cost (credit), and transition asset (obligation). + References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanAmountToBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossNextFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition 1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. + 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 (a) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Projected Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6522206 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Postretirement Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503904 + Details
Name: | us-gaap_DefinedBenefitPlanBenefitObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. + 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 (m) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. + 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 (m) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Health Care Cost Trend Rate -URI http://asc.fasb.org/extlink&oid=6514820 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMaximum
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis. + 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 (d)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 + Details
Name: | us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMinimum
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The ultimate trend rate for health care costs. + 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 (l) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Year the ultimate health care cost trend rate is expected to be reached, in CCYY format. + 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 (l) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanYearThatRateReachesUltimateTrendRate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The change in cash surrender or contract value during the period which adjusted the amount of premiums paid in determining the expense or income recognized under the contract for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 30 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6384439&loc=d3e42048-111605 + Details
Name: | us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 Reference 3: 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(9)(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 4: 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(7)(c)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(g)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
Name: | us-gaap_MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Percentage of vesting of share-based compensation awards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
Name: | us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTypeOfDeferredCompensationAxis=kfy_LongTermPerformanceUnitPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=kfy_CSVOfColiContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=kfy_DefinedBenefitPlanOtherAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=kfy_EnhancedWealthAccumulationPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=kfy_SeniorExecutiveIncentivePlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=kfy_DeferredCompensationPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=kfy_MedicalAndLifeInsuranceBenefitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=kfy_LegacyHayMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=kfy_InternationalRetirementPlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=kfy_ExecutiveCapitalAccumulationPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=kfy_DefinedContributionPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=kfy_CompanyOwnedLifeInsuranceHeldInTrustMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |