Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Basic and Diluted:
Net income attributable to UHS	$ 97,190	$ 171,746	$ 569,678	$ 621,630
Less: Net income attributable to unvested restricted share grants	(243)	(317)	(1,414)	(813)
Net income attributable to UHS – basic and diluted	$ 96,947	$ 171,429	$ 568,264	$ 620,817
Weighted average number of common shares - basic	87,952	92,849	89,288	93,639
Net effect of dilutive stock options and grants based on the treasury stock method	403	481	231	459
Weighted average number of common shares and equivalents - diluted	88,355	93,330	89,519	94,098
Earnings per basic share attributable to UHS:	$ 1.10	$ 1.85	$ 6.36	$ 6.63
Earnings per diluted share attributable to UHS:	$ 1.10	$ 1.84	$ 6.35	$ 6.60