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Refer to current value assessment period for past due loans secured against real estate, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of quarters over which historical loss rates are generally reviewed.

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Refers to maturity period of certificates of deposit in other banks, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The maximum number of delinquent payments that a closed-end loan (excluding conventional 1-4 family residential loans and installment and revolving loans secured by real estate) may be delinquent before being charged-off. If a loan is considered uncollectable, it is charged off earlier.

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Number of shares held in portfolio by the entity.

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The frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned generally, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The typical frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Refers to the past due period after which loans must be well secured and in the process of collection to continue accruing interest, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period for which principal and interest payments must remain current for reclassifying nonaccrual loans as accruing loans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Threshold period past due for the initiation of foreclosure proceedings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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Amount of gain on the sale of property that does not qualify for gain recognition as of the balance sheet date.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount after accumulated impairment loss of an asset representing 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 operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Threshold period past due for financing receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Accounting Policies (Details) $ in Thousands	12 Months Ended
Accounting Policies (Details) $ in Thousands	Dec. 31, 2018 USD ($) Payment Quarter Segment shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016
Certificates of Deposits in Other Banks [Abstract]
Maturity period of certificates of deposit in other banks	18 months
Loans [Abstract]
Past due period after which loans must be well secured and in the process of collection to continue accruing interest	90 days
Period of current principal and interest payments for reclassifying nonaccrual loans as accruing loans	6 months
Allowance for Loan and Lease Losses [Abstract]
Number of delinquent monthly payments before loan charge off \| Payment	5
Current value assessment period for past due loans secured against real estate	90 days
Threshold period past due for initiation of foreclosure proceedings	120 days
Historical loan loss review period \| Quarter	12
Goodwill and Core Deposit Intangible [Abstract]
Goodwill	$ 65,490	$ 65,490
Segment Reporting [Abstract]
Number of operating segments \| Segment	1
New Accounting Standards [Abstract]
Equity securities		25,000
Unrealized holding loss on securities		(600)
Deferred gains on sale of other real estate owned		$ 500
Federal corporate income tax rate	21.00%	35.00%	35.00%
Minimum [Member]
Other Real Estate Owned [Abstract]
Typical frequency of periodic reviews	12 months
Maximum [Member]
Other Real Estate Owned [Abstract]
Typical frequency of periodic reviews	18 months
Frequency of periodic reviews in general	24 months
Visa Class B Restricted Stock [Member]
New Accounting Standards [Abstract]
Gain on recognition of fair value of equity securities	$ 1,200
Number of shares held in portfolio (in shares) \| shares	9,918
Buildings [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	40 years
Furniture, Fixtures, and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	2 years
Furniture, Fixtures, and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years
Commercial [Member] \| Unsecured Commercial Loan [Member]
Allowance for Loan and Lease Losses [Abstract]
Charge off threshold for loans considered uncollectible	90 days
Consumer [Member] \| Closed-End Consumer Loan [Member]
Allowance for Loan and Lease Losses [Abstract]
Charge off threshold for loans considered uncollectible	120 days
ASU 2018-03 [Member] \| Visa Class B Restricted Stock [Member]
New Accounting Standards [Abstract]
Gain on recognition of fair value of equity securities	$ 1,200
Number of shares held in portfolio (in shares) \| shares	9,918
ASU 2018-11 [Member]
New Accounting Standards [Abstract]
Lease liability	$ 16,400
Lease right-of-use asset	15,900
Cumulative-effect adjustment to retained earnings	$ 500