Subsequent Event - Additional Information (Detail) - Subsequent Event - Dividend Declared	Jun. 21, 2021 $ / shares
Subsequent Event [Line Items]
Dividends payable, declared date	Jun. 21, 2021
Dividend payable increase in approval percentage	20.00%
Dividends payable, per share amount	$ 0.12
Dividends payable, payable date	Jul. 30, 2021
Dividends declared, record date	Jul. 06, 2021

The percentage increase in dividend approved by the board.

No definition available.

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Namespace Prefix:	kfy_
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Balance Type:	na
Period Type:	instant

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

+ Details

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Period Type:	duration

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- 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

No definition available.

+ Details

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- Details

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- Details

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