Loans - Narrative (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($) category component class contract	Sep. 30, 2018 contract	Sep. 30, 2019 USD ($) category component LoanModifications class contract	Sep. 30, 2018 contract	Sep. 29, 2019 contract	Jun. 29, 2018 contract	Dec. 31, 2018 USD ($)	Jun. 30, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | contract					0	1
Financing receivable individually evaluated for impairment minimum amount			$ 100,000
Individually evaluated for impairment			$ 100,000
Payment delays limit (in days)			90 days
Impaired financing receivable commitment to lend	$ 2,000		$ 2,000
Reasonable period to classify from troubled debt restructuring non performing loans to performing loans (in months)			6 months
Number of loan modifications (in contracts) | contract	1	1	5	5
Investment in residential real estate loan								$ 3,000
Recorded investment	$ 16,453,000		$ 16,453,000				$ 9,599,000
Real estate acquired through foreclosure	731,690		731,690				624,000
Mortgage loans in process of foreclosure, amount	$ 117,184		$ 117,184				$ 167,000
Number of categories considered not criticized and rated as, Pass | category	6		6
Minimum period after which loans are considered as substandard (in days)			90 days
Number of components that represents the allowance for loan losses | component	2		2
Number of classes that groups of loans are collectively evaluated for impairment | class	2		2
Financing Receivable, Modifications, Number of Contracts | LoanModifications			5
Real Estate Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of categories in which real estate loans segmented | category			3
Real Estate Mortgages | Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan modifications (in contracts) | contract	1	0	1	3