Investment Securities, Equity Securities Changes in Fair Value Recognized in Net Income (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, Amortized Cost Basis	$ 2,163	$ 2,110
Equity securities with a readily determinable fair value, at fair value	2,200	2,160
Net gains recognized	12
Less net realized gains on equity securities sold	25
Unrealized losses recognized and still held at period end	(13)
Mutual funds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, Amortized Cost Basis	1,633	1,586
Equity securities with a readily determinable fair value, at fair value	1,547	1,542
Trust preferred securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, Amortized Cost Basis	49	49
Equity securities with a readily determinable fair value, at fair value	50	50
Equity securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, Amortized Cost Basis	481	475
Equity securities with a readily determinable fair value, at fair value	$ 603	$ 568