XML 50 R39.htm IDEA: XBRL DOCUMENT
v3.25.1

Revenue - Narrative (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 30, 2025 USD ($) segment | Mar. 31, 2024 USD ($) | Dec. 29, 2024 USD ($)
Revenue from Contract with Customer [Line Items] |  |  |
Number of operating segments | segment | 3 |  |
Deferred Fulfillment Costs |  |  |
Revenue from Contract with Customer [Line Items] |  |  |
Capitalized contract cost, net | $ 0.7 |  | $ 1.8
Capitalized contract cost, amortization | $ 1.2 | $ 2.4 |

X
- Definition [Line Items] for Revenue from Contract with Customer [Table] + References No definition available. + Details
Name: | kelya_RevenuefromContractwithCustomerLineItems
Namespace Prefix: | kelya_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 340 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479483/340-40-50-3 + Details
Name: | us-gaap_CapitalizedContractCostAmortization
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 340 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479483/340-40-50-3 + Details
Name: | us-gaap_CapitalizedContractCostNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 49 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-49 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-18 + Details
Name: | us-gaap_NumberOfOperatingSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_CapitalizedContractCostAxis=kelya_DeferredFulfillmentCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |