Existing Lease Terms and Renewal Options for Each of UHS Hospital Facilities (Parenthetical) (Detail) - Universal Health Services, Inc	1 Months Ended	9 Months Ended
	Jun. 30, 2018	Sep. 30, 2018 Time RenewalOption
Operating Leased Assets [Line Items]
Number of renewal options at existing lease rates		3
McAllen Medical Center
Operating Leased Assets [Line Items]
Number of renewal options at existing lease rates		1
Renewal options term at existing lease rates	5 years	5 years
Renewal options at existing lease rates expiration year		2031
Extended lease terms at existing lease rates	2026-12	2026-12
Wellington Regional Medical Center And Southwest Healthcare System
Operating Leased Assets [Line Items]
Number of renewal options at fair market value lease rates | RenewalOption		2
Renewal options term at fair market value lease rates		5 years
Wellington Regional Medical Center And Southwest Healthcare System | Maximum
Operating Leased Assets [Line Items]
Renewal options at fair market value lease rates expiration year		2031
Wellington Regional Medical Center And Southwest Healthcare System | Minimum
Operating Leased Assets [Line Items]
Renewal options at fair market value lease rates expiration year		2022