Investment Securities, Equity Securities Changes in Fair Value Recognized in Net Income (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, Amortized Cost Basis	$ 2,150		$ 2,110
Equity securities with a readily determinable fair value, at fair value	2,188		2,160
Net gains recognized	(11)	$ 0
Less net gains recognized on equity securities sold	23
Unrealized losses recognized and still held at period end	(12)
Mutual funds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, Amortized Cost Basis	1,623		1,586
Equity securities with a readily determinable fair value, at fair value	1,545		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	478		475
Equity securities with a readily determinable fair value, at fair value	$ 593		$ 568