Sale of Corporate Headquarters	9 Months Ended
Sep. 30, 2021
Leases [Abstract]
Sale of Corporate Headquarters	Sale of Corporate HeadquartersOn May 19, 2021, Kforce completed the sale of its corporate headquarters, which had a net book value of $21.7 million, to an independent third party. Kforce received net proceeds of $23.7 million and recognized a gain on the sale in the amount of $2.0 million, which is recorded in SG&A expenses.

The entire disclosure for sale leaseback transaction. Includes, but is not limited to, terms and conditions of transaction and gain (loss) from transaction.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-URI http://asc.fasb.org/subtopic&trid=2209073

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 40
-URI http://asc.fasb.org/subtopic&trid=77888253

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