Investments - Schedule of Direct Financing Lease Receivables (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Net Investment In Leases [Abstract]
Minimum lease payments receivable	$ 4,359	$ 4,518
Estimated unguaranteed residual value of leased assets	270	270
Unearned income from leased assets	(1,939)	(2,063)
Net investment	$ 2,690	$ 2,725

Amount of deferred selling profit from direct financing lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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

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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.

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- Definition

Amount of net investment in direct financing lease.

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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.

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