Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parentheticals) - shares	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Additional Paid-in Capital [Member]
Conversion of subordinated debt, shares (in shares)	1,624,614	36,922
Common Stock [Member]
Options exercised (in shares)	108,975	94,800
Options exercised (in shares)	108,975	94,800

Number of share options (or share units) exercised during the current period.

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Period Type:	duration