Summary of Capital Expenditures Including Accrued Amounts (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Total capital expenditures	$ 29,173	$ 22,633	$ 95,425	$ 43,839
Safety
Segment Reporting Information [Line Items]
Total capital expenditures	13,382	11,592	24,852	23,834
Community
Segment Reporting Information [Line Items]
Total capital expenditures	1,272	7,680	8,419	13,120
Properties
Segment Reporting Information [Line Items]
Total capital expenditures	12,708	2,463	53,702	5,557
Corporate and Other
Segment Reporting Information [Line Items]
Total capital expenditures	$ 1,811	$ 898	$ 8,452	$ 1,328