Discontinued Operations - Narrative (Details) - USD ($) $ in Thousands			3 Months Ended			6 Months Ended
	Jun. 07, 2019	Apr. 01, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of discontinued operations						$ 80,004	$ 0
Deferred tax assets, net			$ 6,238			6,238		$ 7,147
Cash provided by (used in) operating activities for discontinued operations						5,100	(2,700)
Cash provided by (used in) investing activities for discontinued operations						118,900	(800)
Discontinued Operations, Disposed of by Sale | Kforce Government Solutions, Inc.("KGS")
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total cash purchase price		$ 115,000
Gain on sale of discontinued operations		72,300
Transaction costs		$ 9,600
Deferred tax assets, net				$ 18,500
Tax expense (benefit)			18,500	$ (18,500)
Discontinued Operations, Disposed of by Sale | TraumaFX
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total cash purchase price	$ 18,400
Gain on sale of discontinued operations	7,700
Transaction costs	$ 2,200
Contingent consideration paid			600
Discontinued Operations, Disposed of by Sale | GS segment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of discontinued operations			80,004		$ 0	80,004	0
Tax expense (benefit)			$ 20,999		$ 374	$ 2,998	$ 787