Acquisitions Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($)
H2M Group [Member]
Business Combination, Consideration Transferred	$ 38.5
Expected Goodwill Tax Amortization Period	15 years
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	17 years
Kforce Government Solutions [Member]
Business Combination, Consideration Transferred	$ 114.6
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	19 years
Customer Relationships [Member] \| H2M Group [Member]
Finite-Lived Intangible Assets Acquired	$ 9.6
Finite-Lived Intangible Asset, Useful Life	20 years
Customer Relationships [Member] \| Kforce Government Solutions [Member]
Finite-Lived Intangible Assets Acquired	$ 33.1
Finite-Lived Intangible Asset, Useful Life	20 years
Backlog [Member] \| H2M Group [Member]
Finite-Lived Intangible Assets Acquired	$ 2.3
Finite-Lived Intangible Asset, Useful Life	2 years
Backlog [Member] \| Kforce Government Solutions [Member]
Finite-Lived Intangible Assets Acquired	$ 1.6
Finite-Lived Intangible Asset, Useful Life	1 year

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
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