Investment in Rental Property and Lease Arrangements - Minimum Future Rental Receipts Required under Non-cancelable Direct Financing Leases (Detail) $ in Thousands	Dec. 31, 2017 USD ($)
Direct Financing Leases Lease Receivable Fiscal Year Maturity [Abstract]
2018	$ 3,857
2019	3,931
2020	4,037
2021	4,126
2022	4,211
Thereafter	57,727
Minimum future rental receipts required under non-cancelable direct financing leases	$ 77,889

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Direct financing leases, lease receivable payments to be received.

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Direct financing leases, lease receivable payments to be received five years.

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Direct financing leases, lease receivable payments to be received four years.

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Direct financing leases lease receivable payments to be received, next twelve months.

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Direct financing leases, lease receivable payments to be received thereafter.

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Direct financing leases, lease receivable payments to be received three years.

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Direct financing leases, lease receivable payments to be received two years.

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