Segment Information - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2020 Facility Bed State
Segment Reporting Information [Line Items]
Number of facilities | Facility	588
Number of beds | Bed	18,200
Number of operating states | State	40
U.S. Facilities [Member]
Segment Reporting Information [Line Items]
Number of facilities | Facility	228
Number of beds | Bed	9,600
Number of operating states | State	40
U.K. Facilities [Member]
Segment Reporting Information [Line Items]
Number of facilities | Facility	360
Number of beds | Bed	8,700