Acquisitions (Details 1) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Sep. 30, 2018	Dec. 31, 2016
Acquisitions
Investment properties	$ 2,055	$ 2,380
Investment in other company	1,806	$ 1,806
Less: Noncontrolling interest	(150)
Total assets acquired at fair value	5,118
Impairment of investment in other company (*)	(1,439)
Total asset value as of December 31, 2017	$ 4,256

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- Definition

Amount related to investment in other company.

+ References

No definition available.

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- Definition

Amount of investment property equivalents.

+ References

No definition available.

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- Definition

This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount of assets acquired at the acquisition date.

+ References

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-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562

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