Credit Facilities - Federal Home Loan Bank Advances (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Advances from Federal Home Loan Banks
Outstanding balance	$ 49,160	$ 43,489
Federal Home Loan Bank of Atlanta
Advances from Federal Home Loan Banks
Credit facility from FHLB	189,800
Remaining credit availability	140,600
Outstanding balance	49,160	43,489
Average short-term borrowings	4,900	1,400
Principal balances outstanding on pledged loans	156,800	135,300
Federal Home Loan Bank of Atlanta \| FHLB loan maturing June 2019
Advances from Federal Home Loan Banks
Outstanding balance		$ 15,000
Interest rate (as a percent)		1.51%
Federal Home Loan Bank of Atlanta \| FHLB advance maturing June 2020
Advances from Federal Home Loan Banks
Outstanding balance	$ 15,000
Interest rate (as a percent)	2.09%
Federal Home Loan Bank of Atlanta \| FHLB advance maturing November 2020 with 3.04%
Advances from Federal Home Loan Banks
Outstanding balance	$ 5,000	$ 5,000
Interest rate (as a percent)	3.04%	3.04%
Federal Home Loan Bank of Atlanta \| FHLB advance maturing November 2020 with 2.91%
Advances from Federal Home Loan Banks
Outstanding balance	$ 5,000	$ 5,000
Interest rate (as a percent)	2.91%	2.91%
Federal Home Loan Bank of Atlanta \| FHLB advance maturing April 2021
Advances from Federal Home Loan Banks
Outstanding balance	$ 6,000
Interest rate (as a percent)	2.44%
Federal Home Loan Bank of Atlanta \| FHLB advance maturing May 2021
Advances from Federal Home Loan Banks
Outstanding balance	$ 10,000	$ 10,000
Interest rate (as a percent)	2.68%	2.68%
Federal Home Loan Bank of Atlanta \| FHLB advance maturing October 2022
Advances from Federal Home Loan Banks
Outstanding balance	$ 5,000	$ 5,000
Interest rate (as a percent)	3.15%	3.15%
Federal Home Loan Bank of Atlanta \| FHLB advance maturing March 2023
Advances from Federal Home Loan Banks
Outstanding balance	$ 1,607	$ 1,821
Interest rate (as a percent)	1.62%	1.62%
Federal Home Loan Bank of Atlanta \| FHLB advance maturing March 2026
Advances from Federal Home Loan Banks
Outstanding balance	$ 1,553	$ 1,668
Interest rate (as a percent)	1.99%	1.99%

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The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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