Note 6 - Business Segments - Summary of Financial Information by Reporting Segment (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Revenues:
Net patient revenues	$ 363,349,000	$ 279,918,000	$ 724,956,000	$ 565,741,000
Other revenues	11,561,000	11,295,000	23,651,000	22,648,000
Net operating revenues	374,910,000	300,658,000	748,607,000	597,834,000
Government stimulus income	0	9,445,000	0	9,445,000
Costs and expenses:
Salaries, wages, and benefits	226,534,000	180,076,000	454,664,000	363,214,000
Other operating	91,943,000	78,154,000	184,400,000	155,583,000
Rent	11,328,000	10,570,000	22,693,000	20,918,000
Depreciation and amortization	11,015,000	9,338,000	21,993,000	19,924,000
Total costs and expenses	340,820,000	278,138,000	683,750,000	559,639,000
Income/(loss) from operations	34,090,000	22,520,000	64,857,000	38,195,000
Non-operating income (loss)	5,132,000	4,956,000	9,211,000	10,641,000
Interest expense	1,993,000	(0)	4,099,000	46,000
Unrealized losses on marketable equity securities	(5,061,000)	9,124,000	5,921,000	23,523,000
Income/(loss) before income taxes	32,168,000	36,600,000	75,890,000	72,313,000
Segment Reporting, Reconciling Item, Corporate Nonsegment [Member]
Revenues:
Net patient revenues	0	0	0	0
Other revenues	11,131,000	10,971,000	22,848,000	22,309,000
Net operating revenues	11,131,000	20,416,000	22,848,000	31,754,000
Government stimulus income		9,445,000		9,445,000
Costs and expenses:
Salaries, wages, and benefits	12,710,000	10,721,000	25,999,000	21,960,000
Other operating	1,447,000	4,947,000	4,777,000	7,720,000
Rent	1,919,000	1,741,000	3,842,000	3,411,000
Depreciation and amortization	785,000	769,000	1,571,000	1,537,000
Total costs and expenses	16,861,000	18,178,000	36,189,000	34,628,000
Income/(loss) from operations	(5,730,000)	2,238,000	(13,341,000)	(2,874,000)
Non-operating income (loss)	5,132,000	4,956,000	9,211,000	10,641,000
Interest expense	(0)	(0)	(0)	(0)
Unrealized losses on marketable equity securities	(5,061,000)	9,124,000	5,921,000	23,523,000
Income/(loss) before income taxes	(5,659,000)	16,318,000	1,791,000	31,290,000
Inpatient Services Segment [Member] | Operating Segments [Member]
Revenues:
Net patient revenues	325,012,000	245,385,000	650,490,000	497,638,000
Other revenues	430,000	324,000	803,000	339,000
Net operating revenues	325,442,000	245,709,000	651,293,000	497,977,000
Government stimulus income		0		0
Costs and expenses:
Salaries, wages, and benefits	190,641,000	148,059,000	383,078,000	298,949,000
Other operating	83,450,000	66,813,000	165,319,000	135,496,000
Rent	8,828,000	8,262,000	17,662,000	16,374,000
Depreciation and amortization	10,099,000	8,383,000	20,161,000	18,013,000
Total costs and expenses	293,018,000	231,517,000	586,220,000	468,832,000
Income/(loss) from operations	32,424,000	14,192,000	65,073,000	29,145,000
Non-operating income (loss)	0	0	0	0
Interest expense	1,993,000		4,099,000	46,000
Unrealized losses on marketable equity securities	0	0	0	0
Income/(loss) before income taxes	30,431,000	14,192,000	60,974,000	29,099,000
Homecare Services Segment [Member] | Operating Segments [Member]
Revenues:
Net patient revenues	38,337,000	34,533,000	74,466,000	68,103,000
Other revenues	0	0	0	0
Net operating revenues	38,337,000	34,533,000	74,466,000	68,103,000
Government stimulus income		0		0
Costs and expenses:
Salaries, wages, and benefits	23,183,000	21,296,000	45,587,000	42,305,000
Other operating	7,046,000	6,394,000	14,304,000	12,367,000
Rent	581,000	567,000	1,189,000	1,133,000
Depreciation and amortization	131,000	186,000	261,000	374,000
Total costs and expenses	30,941,000	28,443,000	61,341,000	56,179,000
Income/(loss) from operations	7,396,000	6,090,000	13,125,000	11,924,000
Non-operating income (loss)	0	0	0	0
Interest expense	(0)	(0)	(0)	(0)
Unrealized losses on marketable equity securities	0	0	0	0
Income/(loss) before income taxes	$ 7,396,000	$ 6,090,000	$ 13,125,000	$ 11,924,000