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, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Basic and Diluted:
Net income attributable to UHS	$ 238,320	$ 226,052	$ 472,488	$ 449,884
Less: Net income attributable to unvested restricted share grants	(656)	(392)	(1,171)	(496)
Net income attributable to UHS – basic and diluted	$ 237,664	$ 225,660	$ 471,317	$ 449,388
Weighted average number of common shares - basic	89,136	93,842	89,956	94,034
Net effect of dilutive stock options and grants based on the treasury stock method	99	439	145	448
Weighted average number of common shares and equivalents - diluted	89,235	94,281	90,101	94,482
Earnings per basic share attributable to UHS:	$ 2.67	$ 2.40	$ 5.24	$ 4.78
Earnings per diluted share attributable to UHS:	$ 2.66	$ 2.39	$ 5.23	$ 4.76