Consolidated Statements of Changes in Stockholders' Equity (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
AOCI Attributable to Parent [Member]
Other comprehensive income (loss), tax	$ (635)	$ 369	$ (402)
Retained Earnings [Member]
Cash dividend, per share (in dollars per share)	$ 1.21	$ 1.17	$ 1.16
Other comprehensive income (loss), tax	$ (635)	$ 369	$ (402)

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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