Operating and Direct Financing Leases - Components of Net Investments in Direct Financing Leases (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Leases [Abstract]
Total minimum lease payments to be received	$ 777,334	$ 855,655
Estimated unguaranteed residual value of leased properties	203,465	203,465
Initial direct costs and other	393	428
Less unearned revenue	(320,598)	(375,419)
Total	660,594	684,129
Less current portion	(154,759)	(26,542)
Long-term portion	$ 505,835	$ 657,587

The net amount due within one year of the balance sheet date or the normal operating cycle, if longer, consisting of: (a) minimum lease payments due on direct financing leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs, less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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- Definition

The net amount due after one year of the balance sheet date or beyond the normal operating cycle, if longer, consisting of: (a) minimum lease payments due on direct financing leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

+ References

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- Definition

The net investment in direct financing leases as of the balance sheet date consisting of: (a) minimum lease payments due on direct financing leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

+ References

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- Definition

The remaining (unamortized) difference between the gross investment in a direct financing lease and the cost or carrying amount, if different, of the leased property as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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- Definition

Remaining unamortized costs as of the balance sheet date that were essential to acquiring the lease, and that would not otherwise have been incurred without the lease agreement, including evaluating the lessee's credit condition, guarantees, and collateral and costs incurred negotiating, processing, and closing the lease agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=6748888&loc=d3e40246-112709

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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- Definition

Amount of remaining payments as of the balance sheet date that lessees are obligated to make or can be required to make under direct financing leases, including any guarantee of residual value and executory costs. The amount also includes any guaranteed rental payments by an unrelated third-party provided that are financially capable of making such payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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- Definition

The estimate of the lease property's economic value at the end of the direct financing lease term excluding any amounts guaranteed by either the lessee or a third-party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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- References

No definition available.

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