Concentrations and Credit Risks (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Concentrations and Credit Risks (Textual)
Fair value of the Company's investment portfolio	100.00%
Total assets [Member]
Concentrations and Credit Risks (Textual)
Percentage of company's total assets	28.20%	80.40%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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