Note 9 - Goodwill and Other Intangible Assets - (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill, Ending Balance	$ 49,488,000	$ 6,824,000
Goodwill, Impaired, Accumulated Impairment Loss	0
Amortization of Intangible Assets, Total	$ 559,000	$ 276,000	$ 276,000

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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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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