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Business Segment Information (Details Textual) | 9 Months Ended
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Sep. 30, 2018 Segment
Business Segment Information (Textual) |
Number of reportable segments | 3
GEIC [Member] |
Business Segment Information (Textual) |
Company's investment, ownership percentage in subsidiary | 99.30%
GRE [Member] |
Business Segment Information (Textual) |
Company's investment, ownership percentage in subsidiary | 100.00%
GOGAS [Member] |
Business Segment Information (Textual) |
Company's investment, ownership percentage in subsidiary | 97.00%
Afek [Member] |
Business Segment Information (Textual) |
Company's investment, ownership percentage in subsidiary | 86.10%

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- References No definition available. + Details
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Period Type: | duration

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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
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Period Type: | duration

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- Definition Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions. + References No definition available. + Details
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- Details
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Period Type: |

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- Details
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- Details
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Namespace Prefix: |
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Period Type: |

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |