GOODWILL, TRADE NAMES, AND OTHER INTANGIBLE ASSETS - Goodwill Rollforward (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Goodwill [Roll Forward]
Aggregate goodwill acquired, beginning balance	$ 483,629
Accumulated impairment loss, beginning balance	(310,472)
Goodwill, net of impairment loss, beginning balance	163,268
Goodwill acquisition adjustments	(21,748)
Aggregate goodwill acquired, ending balance	461,881
Accumulated impairment loss, ending balance	(310,472)
Goodwill, net of impairment loss, ending balance	141,520
Sale of business
Goodwill [Roll Forward]
Aggregate goodwill acquired, beginning balance	9,889
Aggregate goodwill acquired, ending balance	9,889
Nurse And Allied Staffing
Goodwill [Roll Forward]
Aggregate goodwill acquired, beginning balance	405,008
Accumulated impairment loss, beginning balance	(269,874)
Goodwill, net of impairment loss, beginning balance	125,245
Goodwill acquisition adjustments	(6,648)
Aggregate goodwill acquired, ending balance	398,360
Accumulated impairment loss, ending balance	(269,874)
Goodwill, net of impairment loss, ending balance	118,597
Nurse And Allied Staffing | Sale of business
Goodwill [Roll Forward]
Aggregate goodwill acquired, beginning balance	9,889
Aggregate goodwill acquired, ending balance	9,889
Physician Staffing
Goodwill [Roll Forward]
Aggregate goodwill acquired, beginning balance	78,621
Accumulated impairment loss, beginning balance	(40,598)
Goodwill, net of impairment loss, beginning balance	38,023
Goodwill acquisition adjustments	(15,100)
Aggregate goodwill acquired, ending balance	63,521
Accumulated impairment loss, ending balance	(40,598)
Goodwill, net of impairment loss, ending balance	22,923
Physician Staffing | Sale of business
Goodwill [Roll Forward]
Aggregate goodwill acquired, beginning balance	0
Aggregate goodwill acquired, ending balance	$ 0