Note 4 - Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2013
Goodwill, Impairment Loss	$ 0
Finite-lived Intangible Assets, Fair Value Disclosure	3,500	$ 3,100
Loans Serviced for Others Outstanding Principal Balance	331,800	$ 344,500
Core Deposits [Member]
Finite-Lived Intangible Assets, Net, Ending Balance	1,100
Indiana Bank [Member] \| Commercial Banking [Member]
Goodwill, Ending Balance	$ 682
THE BANCorp [Member] \| Core Deposits [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles			$ 2,500

Represents the outstanding principal balances of loans serviced for others.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

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Fair value portion of assets, excluding financial assets, that lack physical substance, having a limited useful life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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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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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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