Summary of Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021		Dec. 31, 2020
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 3,882,715		$ 3,869,760
Goodwill acquired during the period	55,406		127
Goodwill divested during the period	0		0
Adjustments to goodwill	24,503	[1]	12,828	[2]
Goodwill, Ending Balance	3,962,624		3,882,715
Acute Care Services
Goodwill [Line Items]
Goodwill, Beginning Balance	447,021		448,415
Goodwill acquired during the period	55,406		127
Goodwill divested during the period	0		0
Adjustments to goodwill	13,509	[1]	(1,521)	[2]
Goodwill, Ending Balance	515,936		447,021
Behavioral Health Services
Goodwill [Line Items]
Goodwill, Beginning Balance	3,435,694		3,421,345
Goodwill acquired during the period	0		0
Goodwill divested during the period	0		0
Adjustments to goodwill	10,994	[1]	14,349	[2]
Goodwill, Ending Balance	$ 3,446,688		$ 3,435,694

[1] Adjustments to goodwill during 2021 consist of the following: $13.5 million in Acute Care Services consists primarily of a measurement period adjustment to the preliminary purchase price allocation related to a 2020 acquisition; and the $11.0 million in Behavioral Health Services consists of $16.3 million recorded in connection with a third party minority ownership interest in a majority owned joint venture that constructed and owns a recently opened behavioral health facility, partially offset by a $5.3 million decrease related to foreign currency translation adjustments.

[2] The changes in the Behavioral Health Services’ goodwill consists primarily of foreign currency translation adjustments.