Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Basic and Diluted:
Net income attributable to UHS	$ 325,024	$ 251,929	$ 534,115	$ 393,966
Less: Net income attributable to unvested restricted share grants	(661)	(824)	(1,213)	(1,197)
Net income attributable to UHS – basic and diluted	$ 324,363	$ 251,105	$ 532,902	$ 392,769
Weighted average number of common shares - basic	84,224	84,632	84,503	85,422
Net effect of dilutive stock options and grants based on the treasury stock method	1,400	427	1,207	335
Weighted average number of common shares and equivalents - diluted	85,624	85,059	85,710	85,757
Earnings per basic share attributable to UHS:	$ 3.85	$ 2.97	$ 6.31	$ 4.60
Earnings per diluted share attributable to UHS:	$ 3.79	$ 2.95	$ 6.22	$ 4.58