Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 797,883	$ 771,312	$ 747,171
Other comprehensive income (loss):
Unrealized derivative gains on cash flow hedges	(2,805)	6,679	1,438
Amortization of terminated hedge	0	0	(167)
Minimum pension liability	(6,892)	4,070	13,356
Foreign currency translation adjustment	9,718	(2,169)	(2,229)
Other	4,398	26,678	(10,038)
Other comprehensive income before tax	4,419	35,258	2,360
Income tax expense related to items of other comprehensive income	8,905	2,664	4,648
Total other comprehensive income (loss), net of tax	(4,486)	32,594	(2,288)
Comprehensive income	793,397	803,906	744,883
Less: Comprehensive income attributable to noncontrolling interests	18,178	19,009	44,762
Comprehensive income attributable to UHS	$ 775,219	$ 784,897	$ 700,121