Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
AOCI Attributable to Parent [Member]
Other comprehensive income (loss), tax	$ (517)	$ (220)	$ (1,141)	$ 1,234
Retained Earnings [Member]
Cash dividend, per share (in dollars per share)			$ 0.58	$ 0.56
Cash dividend, per share (in dollars per share)	$ 0	$ 0	$ 0.58	$ 0.56

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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