Quarterly Results (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Net revenues	$ 2,896,247	$ 2,822,453	$ 2,855,168	$ 2,804,391	$ 2,754,496	$ 2,648,913	$ 2,681,353	$ 2,687,516	$ 11,378,259	$ 10,772,278	$ 10,409,865
Net income	248,010	100,870	241,265	237,398	163,622	174,881	230,711	228,669	827,543	797,883	771,312
Less: Net income attributable to noncontrolling interests	2,834	3,680	2,945	3,230	5,547	3,135	4,659	4,837	12,689	18,178	19,009
Net income attributable to UHS	$ 245,176	$ 97,190	$ 238,320	$ 234,168	$ 158,075	$ 171,746	$ 226,052	$ 223,832	$ 814,854	$ 779,705	$ 752,303
Earnings per share attributable to UHS-Basic:
Total basic earnings per share	$ 2.81	$ 1.10	$ 2.67	$ 2.57	$ 1.71	$ 1.85	$ 2.40	$ 2.37	$ 9.16	$ 8.35	$ 7.86
Earnings per share attributable to UHS-Diluted:
Total diluted earnings per share	$ 2.79	$ 1.10	$ 2.66	$ 2.57	$ 1.70	$ 1.84	$ 2.39	$ 2.36	$ 9.13	$ 8.31	$ 7.81