Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Basic and diluted:
Net Income	$ 987,632	$ 952,790	$ 827,543
Less: Net (income) loss attributable to noncontrolling interest	3,958	(8,837)	(12,689)
Less: Net income attributable to unvested restricted share grants	(2,059)	(2,981)	(2,028)
Net income attributable to UHS—basic and diluted	$ 989,531	$ 940,972	$ 812,826
Basic earnings per share attributable to UHS:
Weighted average number of common shares—basic	82,519	85,061	88,762
Total basic earnings per share	$ 11.99	$ 11.06	$ 9.16
Diluted earnings per share attributable to UHS:
Weighted average number of common shares—basic	82,519	85,061	88,762
Net effect of dilutive stock options and grants based on the treasury stock method	1,173	526	278
Weighted average number of common shares and equivalents—diluted	83,692	85,587	89,040
Total diluted earnings per share	$ 11.82	$ 10.99	$ 9.13