Leases - Future Contractual Minimum Annual Rentals Receivable (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
Operating leases
Operating leases, 2019	$ 102,928
Operating leases, 2020	102,693
Operating leases, 2021	99,593
Operating leases, 2022	99,184
Operating leases, 2023	99,223
Operating leases, Thereafter	678,106
Operating leases, Total	1,181,727
Direct financing leases
Financing Leases	12,864
Direct financing leases, 2020	13,156
Direct financing leases, 2021	13,339
Direct financing leases, 2022	13,420
Direct financing leases, 2023	13,467
Direct financing leases, Thereafter	73,030
Direct financing leases, Total	$ 139,276