Represents the aggregate number of full service locations.

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Represents the number of quarters for the look-back period for the critical accounting policy related to allowance and provision for loan losses.

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Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

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No definition available.

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

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The number of derivative instruments of a particular group held by the entity.

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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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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Amount of lessee's right to use underlying asset under operating lease.

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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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Amount of unrecognized tax benefits.

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Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2016 USD ($)
Period Look-back, Quarters		32	28
Allowance for Loan and Lease Losses, Period Increase (Decrease), Total		$ 1,300
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ 5,900	5,900
Unrecognized Tax Benefits, Ending Balance	$ 40	$ 29	$ 40		$ 40
Aggregate Number of Full Service Branche Locations		38
Number of Operating Segments		2
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect
Scenario, Forecast [Member]
Operating Lease, Right-of-Use Asset				$ 16,600
Operating Lease, Liability, Total				$ 17,900
Accounting Standards Update 2018-02 [Member]
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect		$ 506
Fair Value Hedging [Member]
Derivative, Number of Instruments Held, Total	0	0	0
Minimum [Member]
Property, Plant and Equipment, Useful Life		3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life		40 years