Supplemental Cash Flow Information Related to Leases (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2019 USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 52,036
Operating cash flows from finance leases	1,108
Financing cash flows from finance leases	907
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	359,329
Finance leases	$ 0