Summary of Significant Accounting Policies - Restricted Investment in Bank Stock (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Federal Home Loan Bank (FHLB)
Restricted Investment in Bank Stock
FHLB stock	$ 8,000	$ 6,900
Investment impairment	0	0
Atlantic Central Bankers Bank
Restricted Investment in Bank Stock
Investment	$ 50	$ 50

Amount of impairment loss on investment in equity security without readily determinable fair value.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 325
-Section 45
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No definition available.

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

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