Segments - Schedule of Financial Information Attributable to the Company's Business Segments (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Segment Reporting Information [Line Items]
Service revenue, net	$ 686,925,000		$ 647,782,000	$ 2,048,338,000	$ 1,850,472,000
Grant income	551,000		789,000	4,649,000	4,587,000
Service expense	579,214,000		534,563,000	1,718,735,000	1,498,108,000
General and administrative expense	70,142,000		75,889,000	229,095,000	232,108,000
Depreciation and amortization	26,077,000		25,672,000	77,679,000	74,376,000
Impairment of goodwill	0	$ 183,100,000	0	183,100,000	0
Operating income (loss)	12,043,000		12,447,000	(155,622,000)	50,467,000
Equity in net income (loss) of investee, net of tax	(160,000)		(26,448,000)	2,821,000	(28,020,000)
Equity investment	45,207,000		43,477,000	45,207,000	43,477,000	$ 41,303,000
Goodwill	785,554,000		968,420,000	785,554,000	968,420,000	968,654,000
Total assets	1,763,086,000		1,989,845,000	1,763,086,000	1,989,845,000	1,944,272,000
NEMT
Segment Reporting Information [Line Items]
Service revenue, net	485,951,000		459,796,000	1,452,389,000	1,309,449,000
Grant income	0		0	0	0
Service expense	428,021,000		394,981,000	1,277,604,000	1,100,801,000
General and administrative expense	25,433,000		31,815,000	87,645,000	102,736,000
Depreciation and amortization	6,814,000		7,079,000	20,319,000	21,576,000
Impairment of goodwill				0
Operating income (loss)	25,683,000		25,921,000	66,821,000	84,336,000
Equity in net income (loss) of investee, net of tax	142,000		208,000	984,000	143,000
Equity investment	1,552,000		208,000	1,552,000	208,000
Goodwill	135,186,000		135,186,000	135,186,000	135,186,000	135,186,000
Total assets	512,032,000		517,930,000	512,032,000	517,930,000
PCS
Segment Reporting Information [Line Items]
Service revenue, net	179,979,000		169,226,000	534,435,000	491,661,000
Grant income	551,000		789,000	4,649,000	4,587,000
Service expense	143,078,000		132,746,000	417,636,000	379,423,000
General and administrative expense	20,252,000		22,057,000	63,480,000	68,536,000
Depreciation and amortization	12,850,000		12,919,000	38,590,000	37,976,000
Impairment of goodwill		137,300,000		137,331,000
Operating income (loss)	4,350,000		2,293,000	(117,953,000)	10,313,000
Equity in net income (loss) of investee, net of tax	0		0	0	0
Equity investment	0		0	0	0
Goodwill	415,444,000		552,775,000	415,444,000	552,775,000	552,775,000
Total assets	774,731,000		962,425,000	774,731,000	962,425,000
RPM
Segment Reporting Information [Line Items]
Service revenue, net	19,779,000		18,760,000	57,702,000	49,362,000
Grant income	0		0	0	0
Service expense	6,934,000		6,836,000	20,129,000	17,884,000
General and administrative expense	5,685,000		5,816,000	16,781,000	17,520,000
Depreciation and amortization	6,174,000		5,467,000	18,087,000	14,201,000
Impairment of goodwill		$ 45,800,000		45,769,000
Operating income (loss)	986,000		641,000	(43,064,000)	(243,000)
Equity in net income (loss) of investee, net of tax	0		0	0	0
Equity investment	0		0	0	0
Goodwill	234,894,000		280,429,000	234,894,000	280,429,000	280,663,000
Total assets	346,257,000		402,929,000	346,257,000	402,929,000
Corporate and Other
Segment Reporting Information [Line Items]
Service revenue, net	1,216,000		0	3,812,000	0
Grant income	0		0	0	0
Service expense	1,181,000		0	3,366,000	0
General and administrative expense	18,772,000		16,201,000	61,189,000	43,316,000
Depreciation and amortization	239,000		207,000	683,000	623,000
Impairment of goodwill				0
Operating income (loss)	(18,976,000)		(16,408,000)	(61,426,000)	(43,939,000)
Equity in net income (loss) of investee, net of tax	(302,000)		(26,656,000)	1,837,000	(28,163,000)
Equity investment	43,655,000		43,269,000	43,655,000	43,269,000
Goodwill	30,000		30,000	30,000	30,000	$ 30,000
Total assets	$ 130,066,000		$ 106,561,000	$ 130,066,000	$ 106,561,000