Parent Corporation Only Statements (Statements of Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Statement of Income Captions [Line Items]
Net income	$ 16,500	$ 16,404	$ 15,419
Other comprehensive income:
Unrealized holding gains (losses) arising during period	(417)	(816)	(528)
Less: reclassification adjustment for gains included in net income	0	(52)	(188)
Unrealized gains on interest rate swaps	64	0	0
Tax effect	146	304	255
Comprehensive income	16,293	15,840	14,958
Parent [Member]
Other comprehensive income:
Unrealized holding gains (losses) arising during period	(417)	(816)	(528)
Less: reclassification adjustment for gains included in net income	0	(52)	(188)
Unrealized gains on interest rate swaps	64	0	0
Tax effect	146	304	255
Net of tax amount	(207)	(564)	(461)
Comprehensive income	16,293	15,840	14,958
Parent [Member]
Condensed Statement of Income Captions [Line Items]
Net income	$ 16,500	$ 16,404	$ 15,419