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Investment in Rental Property and Lease Arrangements - Net Investment in Direct Financing Leases (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Leases [Abstract] |  |
Minimum lease payments to be received | $ 77,889 | $ 90,447
Estimated unguaranteed residual values | 19,758 | 22,335
Less unearned revenue | (56,030) | (65,511)
Net investment in direct financing leases | $ 41,617 | $ 47,271

X
- Definition Amount of deferred selling profit from direct financing lease. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919379-209981 + Details
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- Definition Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term, guaranteed by lessee or other third party unrelated to lessor, from direct financing lease. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919379-209981 + Details
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- Definition Amount of net investment in direct financing lease. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919379-209981 + Details
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- Definition Present value expected to be derived from underlying asset, following end of lease term, not guaranteed by lessee or other third party unrelated to lessor. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919379-209981 + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- References No definition available. + Details
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