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Investment Securities (Reconciliation of Credit Related Impairment Charges ) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of credit-related impairment charges on investments recognized in earnings
Impairment charges on available-for-sale investment securities, after tax	$ 354,000	$ 230,100
Available-for-sale investments
Reconciliation of credit-related impairment charges on investments recognized in earnings
Balance at the beginning	13,931,000	13,577,000
Sale of other-than-temporarily impaired available-for-sale securities during period	$ (13,931,000)
Impairment charges recognized during period		(354,000)
Balance at the end		$ 13,931,000

X

- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis after taxes. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

No definition available.

+ Details

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X

- Definition

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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X

- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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X

- Definition

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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X

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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