Debt Instrument, Interest Rate, Variable, Interest Rate Floor

No definition available.

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- Definition

Line Of Credit, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Covenant Terms, Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Covenant Terms, Leverage Ratio

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Debt Covenant, Leverage Ratio Threshold

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Debt Covenant, Repurchase Of Equity Securities

+ References

No definition available.

+ Details

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Namespace Prefix:	kfrc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line Of Credit Facility, Debt Covenant, Threshold, Unrestricted Cash

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Subsequent Events (Details) - USD ($) $ in Millions	Nov. 05, 2025	Oct. 20, 2021
Revolving Credit Facility \| Subsequent Event
Subsequent Event [Line Items]
Initial maximum borrowing capacity	$ 200.0
Accordion feature, increase limit	$ 150.0
Debt Instrument, Interest Rate, Variable, Interest Rate Floor	0.00%
Line of Credit Facility, Debt Covenant, Repurchase Of Equity Securities	$ 25.0
Line Of Credit Facility, Debt Covenant, Threshold, Unrestricted Cash	$ 25.0
Line Of Credit Facility, Debt Covenant, Leverage Ratio Threshold	300.00%
Revolving Credit Facility \| Subsequent Event \| Base Rate
Subsequent Event [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Revolving Credit Facility \| Subsequent Event \| Federal Funds Rate
Subsequent Event [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Revolving Credit Facility \| Subsequent Event \| Secured Overnight Financing Rate (SOFR)
Subsequent Event [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Revolving Credit Facility \| Subsequent Event \| Minimum
Subsequent Event [Line Items]
Line of Credit Facility, Covenant Terms, Fixed Charge Coverage Ratio	125.00%
Revolving Credit Facility \| Subsequent Event \| Minimum \| Base Rate
Subsequent Event [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.25%
Revolving Credit Facility \| Subsequent Event \| Minimum \| Secured Overnight Financing Rate (SOFR)
Subsequent Event [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Revolving Credit Facility \| Subsequent Event \| Maximum
Subsequent Event [Line Items]
Line Of Credit Facility, Covenant Terms, Leverage Ratio	350.00%
Revolving Credit Facility \| Subsequent Event \| Maximum \| Base Rate
Subsequent Event [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.625%
Revolving Credit Facility \| Subsequent Event \| Maximum \| Secured Overnight Financing Rate (SOFR)
Subsequent Event [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.625%
Revolving Credit Facility \| Subsequent Event \| Swingline Loans
Subsequent Event [Line Items]
Initial maximum borrowing capacity	$ 10.0
Revolving Credit Facility \| Subsequent Event \| Letter of Credit
Subsequent Event [Line Items]
Initial maximum borrowing capacity	$ 10.0
Credit Facility \| Revolving Credit Facility
Subsequent Event [Line Items]
Initial maximum borrowing capacity		$ 200.0
Accordion feature, increase limit		$ 150.0