Summary of Significant Accounting Policies - Others (Details)	12 Months Ended
Dec. 31, 2019 USD ($) item $ / shares	Dec. 31, 2018 USD ($) item
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of reportable segments \| item	0
Contract with Customer
Contract assets	$ 0	$ 0
Contract liabilities	$ 0	$ 0
Loans Receivable
Maximum percentage of lending of appraised value of property	80.00%
Restricted Stock Investments
FHLB stock (in dollars per share) \| $ / shares	$ 100
Number of restricted stock investment wrote off \| item		1
Write off of restricted stock investment		$ 100,000
Goodwill and Other Intangible Assets
Number of reporting units \| item	1
Goodwill impairment	$ 0	0
Advertising Costs
Advertising Expense	$ 936,000	1,021,000
Residential Mortgage [Member]
Change in Accounting Estimate
Allowance allocated increased (decreased)		600,000
Commercial [Member]
Change in Accounting Estimate
Allowance allocated increased (decreased)		2,200,000
Commercial Real Estate [Member]
Change in Accounting Estimate
Allowance allocated increased (decreased)		2,700,000
ADC [Member]
Change in Accounting Estimate
Allowance allocated increased (decreased)		$ 1,100,000

Represents maximum percentage of lending of appraised value of property.

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Represents the number of restricted stock investments wrote-off.

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Represents the amount of write-off of federal home loan bank stock.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Amount of increase (decrease) of allowance reserve for credit loss.

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Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer, when right is conditioned on something other than passage of time.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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