XML 63 R47.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Deferred Compensation and Retirement Plans - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Oct. 31, 2018 | Oct. 31, 2017 | Oct. 31, 2018 | Oct. 31, 2017 | Apr. 30, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Increase in market value of the underlying COLI investments |  |  | $ 3,003 | $ 4,227 |
Recognized investment income (expense) | $ (4,800) | $ 3,400 | (836) | 6,797 |
Executive Capital Accumulation Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Gain (loss) on deferred compensation plan | (4,300) | 3,500 | $ (200) | 7,200 |
Minimum |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Option to receive employee benefits by quarterly installments periods |  |  | 1 year |  |
Minimum | Executive Capital Accumulation Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Deferred compensation arrangement vesting period |  |  | 4 years |  |
Maximum |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Option to receive employee benefits by quarterly installments periods |  |  | 15 years |  |
Maximum | Executive Capital Accumulation Plan |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Deferred compensation arrangement vesting period |  |  | 5 years |  |
CSV of COLI Contracts |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Gross CSV | 219,200 |  | $ 219,200 |  | $ 186,800
Outstanding policy loans | 96,000 |  | 96,000 |  | $ 66,700
Increase in market value of the underlying COLI investments | $ 1,700 | $ 1,700 | $ 3,000 | $ 4,200 |

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 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 Option to receive employee benefits by quarterly installments periods. + References No definition available. + Details
Name: | kfy_OptionToReceiveEmployeeBenefitsByQuarterlyInstallmentsPeriods
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 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://fasb.org/us-gaap/role/ref/legacyRef -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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_DeferredCompensationArrangementWithIndividualRequisiteServicePeriod1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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 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://fasb.org/us-gaap/role/ref/legacyRef -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 Amount of unrealized and realized gain (loss) on investment in marketable security, excluding other-than-temporary impairment (OTTI). + References No definition available. + Details
Name: | us-gaap_MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
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: |