Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Redeemable Noncontrolling Interest	Class A	Class B	Class C	Class D	Cumulative Dividends	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	UHS Common Stockholders' Equity	Noncontrolling Interest
Balance at Dec. 31, 2018	$ 5,465,793		$ 66	$ 841	$ 7	$ 0	$ (409,156)	$ 5,793,262	$ 4,242	$ 5,389,262	$ 76,531
Balance at Dec. 31, 2018		$ 4,292
Common Stock
Issued/(converted)	2,726			6				2,720		2,726
Repurchased	(137,229)			(10)				(137,219)		(137,229)
Restricted share-based compensation expense	1,523							1,523		1,523
Dividends paid	(9,081)						(9,081)			(9,081)
Stock option expense	15,759							15,759		15,759
Distributions to noncontrolling interests	(9,814)	(500)									(9,814)
Comprehensive income:
Net income to UHS / noncontrolling interests	237,347							234,168		234,168	3,179
Net income attributable to redeemable noncontrolling interest		51
Foreign currency translation adjustments, net of income tax	(12,489)								(12,489)	(12,489)
Unrealized derivative gains on cash flow hedges, net of income tax	(2,224)								(2,224)	(2,224)
Subtotal - comprehensive income	222,634							234,168	(14,713)	219,455	3,179
Subtotal attributable to redeemable noncontrolling interest		51
Balance at Mar. 31, 2019	5,552,311		66	837	7	0	(418,237)	5,910,213	(10,471)	5,482,415	69,896
Balance at Mar. 31, 2019		3,843
Balance at Dec. 31, 2019	5,578,871		66	794	7	0	(462,159)	5,933,504	31,893	5,504,105	74,766
Balance at Dec. 31, 2019		4,333
Common Stock
Issued/(converted)	3,112			2				3,110		3,112
Repurchased	(199,292)			(20)				(199,272)		(199,292)
Restricted share-based compensation expense	2,355							2,355		2,355
Dividends paid	(17,344)						(17,344)			(17,344)
Stock option expense	15,329							15,329		15,329
Distributions to noncontrolling interests	(5,234)	(500)									(5,234)
Comprehensive income:
Net income to UHS / noncontrolling interests	144,339							142,037		142,037	2,302
Net income attributable to redeemable noncontrolling interest		120
Foreign currency translation adjustments, net of income tax	(37,093)								(37,093)	(37,093)
Subtotal - comprehensive income	107,246							142,037	(37,093)	104,944	2,302
Subtotal attributable to redeemable noncontrolling interest		120
Balance at Mar. 31, 2020	5,485,043		$ 66	$ 776	$ 7	$ 0	$ (479,503)	$ 5,897,063	$ (5,200)	$ 5,413,209	$ 71,834
Balance at Mar. 31, 2020	$ 4,000	$ 3,953