v3.8.0.1

Investment in Rental Property and Lease Arrangements - Additional Information (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 USD ($) Property | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Lessor Lease Description [Line Items] |  |  |
Number of real estate properties under operating leases | 513 |  |
Number of real estate properties under direct financing leases | 15 |  |
Number of real estate properties under direct financing leases that include land option | 4 |  |
Lessor, operating lease, existence of option to extend | true |  |
Lessor, direct financing lease, existence of option to extend | true |  |
Depreciation expense on investment in rental property | $ | $ 50,360 | $ 37,976 | $ 25,038
Minimum |  |  |
Lessor Lease Description [Line Items] |  |  |
Lessor operating lease, initial terms | 10 years |  |
Lessor direct financing leases, initial terms | 10 years |  |
Maximum |  |  |
Lessor Lease Description [Line Items] |  |  |
Lessor operating lease, initial terms | 20 years |  |
Lessor direct financing leases, initial terms | 20 years |  |

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- Definition Number of properties classified as direct financing leases. + References No definition available. + Details
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- Definition Number of real estate properties under direct financing leases that include land option. + References No definition available. + Details
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- Definition Indicates (true/false) whether lessor has option to extend 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 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919359-209981 + Details
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- Definition Term of lessor's direct financing lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919359-209981 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Indicates (true/false) whether lessor has option to extend operating lease. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919359-209981 + Details
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- Definition The total depreciation charge recorded for property subject to or held for lease. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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- Definition The number of units (items of property) under operating lease arrangements. + References No definition available. + Details
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