Business Combinations (Information About Acquired ERB Loans Accounted for Under ASC 310-30) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Oct. 01, 2016	Dec. 31, 2015
Interest component of expected cash flows (accretable discount)	$ 196	$ 314
East River Bank (“ERB”) [Member]
Contractually required principal and interest at acquisition			$ 3,142
Contractual cash flows not expected to be collected (nonaccretable discount)			(1,124)
Expected cash flows at acquisition			2,018
Interest component of expected cash flows (accretable discount)			(348)
Fair value of acquired loans			$ 1,670