Summary of Capital Expenditures Including Accrued Amounts (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Total capital expenditures	$ 66,252	$ 21,206
Safety
Segment Reporting Information [Line Items]
Total capital expenditures	11,470	12,242
Community
Segment Reporting Information [Line Items]
Total capital expenditures	7,147	5,440
Properties
Segment Reporting Information [Line Items]
Total capital expenditures	40,994	3,094
Corporate and Other
Segment Reporting Information [Line Items]
Total capital expenditures	$ 6,641	$ 430