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Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands		12 Months Ended
	Feb. 26, 2020 shares	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) Segment	Dec. 31, 2018 USD ($) shares	Sep. 30, 2019 USD ($)
Finite Lived Intangible Assets [Line Items]
Maximum Maturity Period For Cash Equivalents		90 days
Number Of Investment Portfolios					3
Number of Securities Held as Trading Securities					0
Number of Reportable Segments					2	2
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares			68,150				62,150
Operating lease, right-of-use asset		$ 3,543	$ 3,543	$ 3,543	$ 3,543	$ 3,543
Operating lease, liability		3,573	3,573	3,573	3,573	3,573
Revenue, remaining performance obligation, amount		0	0	0	0	0
Contract with customer, liability, total		$ 0	$ 0	0	$ 0	$ 0
Service and Other Charges on Deposit Accounts, Mortgage Fees From Secondary Market Transactions at The Bank ATM Fee Income and Other Noninterest Income [Member]
Finite Lived Intangible Assets [Line Items]
Revenue from Contract with Customer, Including Assessed Tax				$ 3,400			$ 3,200
Accounting Standards Update 2016-02 [Member]
Finite Lived Intangible Assets [Line Items]
Operating lease, right-of-use asset								$ 3,500
Operating lease, liability								$ 3,600
Non-qualified Stock Options [Member] | Subsequent Event [Member]
Finite Lived Intangible Assets [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares	9,200
Restricted Stock [Member] | Subsequent Event [Member]
Finite Lived Intangible Assets [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted | shares	24,660
Core Deposits [Member]
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		7 years					7 years

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