Loans Receivable and Allowance for Loan Losses (Schedule of loans receivable) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 106,365	$ 100,282
Less: Net Deferred Loan Fees	(360)	(380)
Loans in Process	(1,587)	(1,601)
Allowance for Loan Losses	(756)	(768)	$ (756)
Net Loans	103,662	97,533
Real Estate \| Secured by One-to four family residential properties Owner-occupied
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	53,977	52,956
Real Estate \| Secured by One-to four family residential properties Non-owner-occupied
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	14,536	13,485
Real Estate \| Secured by One-to four family residential properties Home Equity Lines of Credit
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	3,790	2,973
Real Estate \| Commercial
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	22,627	21,868
Allowance for Loan Losses	(95)	(113)	(94)
Real Estate \| Land
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	2,288	2,211
Allowance for Loan Losses	(19)	(23)	(56)
Real Estate \| Construction
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	4,241	2,947
Allowance for Loan Losses	(19)	(16)	(8)
Real Estate \| Multi-family
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	2,115	1,524
Allowance for Loan Losses	(6)	(5)	(4)
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	2,534	1,964
Allowance for Loan Losses	(89)	(83)	(48)
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	257	354
Allowance for Loan Losses	$ (23)	$ (9)	$ (1)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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