Acquisitions and Divestitures - Additional Information (Detail) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015 USD ($) Facility Bed	Sep. 30, 2015 USD ($) Bed Hospital	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($) Bed	Dec. 31, 2014 USD ($) Bed	Sep. 30, 2014 USD ($) Facility Bed Hospital	Jun. 30, 2014 USD ($) Bed	Mar. 31, 2014 USD ($) Bed	Dec. 31, 2015 USD ($) Facility $ / shares	Dec. 31, 2014 USD ($) Bed $ / shares	Dec. 31, 2013 USD ($) Facility $ / shares	Dec. 31, 2012 Bed
Business Acquisition [Line Items]
Number of hospitals | Facility									3		3
Indefinite lived Tradenames	$ 124,000								$ 124,000
Net revenues	$ 2,315,239	$ 2,227,655	$ 2,275,204	$ 2,225,353	$ 2,176,291	$ 2,038,717	$ 2,051,766	$ 1,938,314	9,043,451	$ 8,205,088	$ 7,367,873
Unaudited pro forma net revenues									9,170,000	8,350,000
Unaudited pro forma net income attributable to UHS									$ 690,000	$ 545,000
Unaudited pro forma net income attributable to UHS per diluted share | $ / shares									$ 6.85	$ 5.42
Aggregate cash proceeds from divestiture of businesses									$ 3,000	$ 15,000
Aggregate pre-tax net gain on the divestiture											3,080
2013 Divestiture of Assets and Businesses | Peak Behavioral Health Services
Business Acquisition [Line Items]
Net cash proceeds from divestiture of assets and businesses							24,000				37,000
Aggregate pre-tax net gain on the divestiture							$ 3,000				3,000
2012 Divestiture of Assets and Businesses | Peak Behavioral Health Services
Business Acquisition [Line Items]
Number of beds | Bed												104
2015 Acquisitions of Assets and Businesses
Business Acquisition [Line Items]
Acquisition, cash paid									534,000
Net revenues									$ 30,000
Behavioral Health Services
Business Acquisition [Line Items]
Number of beds | Bed				46
Alpha Hospitals Holdings Limited
Business Acquisition [Line Items]
Number of beds | Bed		305
Number of hospitals | Hospital		4
Foundations Recovery Network, LLC
Business Acquisition [Line Items]
Number of beds | Bed	322
Number of facilities | Facility	4
Number of outpatient centers | Facility	8
2014 Acquisitions of Assets and Businesses
Business Acquisition [Line Items]
Acquisition, cash paid										431,000
Unaudited pro forma net revenues										8,280,000
Unaudited pro forma net income attributable to UHS										$ 558,000
Unaudited pro forma net income attributable to UHS per diluted share | $ / shares										$ 5.55
2013 Acquisitions of Assets and Businesses
Business Acquisition [Line Items]
Acquisition, cash paid											13,000
Unaudited pro forma net revenues											7,620,000
Unaudited pro forma net income attributable to UHS											$ 522,000
Unaudited pro forma net income attributable to UHS per diluted share | $ / shares											$ 5.25
Cygnet Health Care Limited
Business Acquisition [Line Items]
Number of beds | Bed						723				124
Number of hospitals | Hospital						15
Number of facilities | Facility						17
Net revenues										$ 175,000
Number of nursing homes | Hospital						2
Acquired Company Two
Business Acquisition [Line Items]
Number of beds | Bed							124
Palo Verde Behavioral Health
Business Acquisition [Line Items]
Number of beds | Bed								48
The Bridgeway
Business Acquisition [Line Items]
Number of beds | Bed					103
Cygnet Hospital-Harrow
Business Acquisition [Line Items]
Number of beds | Bed					44