Computation of Basic and Diluted Earnings per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Basic and Diluted:
Net income attributable to UHS	$ 114,587	$ 71,817	$ 386,212	$ 307,985
Less: Net income attributable to unvested restricted share grants	(43)	(85)	(200)	(379)
Net income attributable to UHS - basic and diluted	$ 114,544	$ 71,732	$ 386,012	$ 307,606
Weighted average number of common shares - basic	98,151	96,817	97,965	96,701
Net effect of dilutive stock options and grants based on the treasury stock method	1,436	794	1,158	1,010
Weighted average number of common shares and equivalents - diluted	99,587	97,611	99,123	97,711
Earnings per basic share attributable to UHS	$ 1.17	$ 0.74	$ 3.94	$ 3.18
Earnings per diluted share attributable to UHS	$ 1.15	$ 0.73	$ 3.89	$ 3.15