Investments - Available-for-Sale (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Investments - Available-for-Sale
Investment securities available for sale	$ 13,797,120	$ 10,801,836
Unrealized gains	21,759	17,415
Unrealized losses	(2,800)	(1,192)
Fair value of investments	$ 13,816,079	$ 10,818,059

Amount of unrealized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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- Definition

Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

+ References

No definition available.

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- References

No definition available.

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