Investment Securities (Detail Textuals) - Security	Mar. 31, 2018	Dec. 31, 2017
Schedule Of Available For Sale and Held To Maturity Securities [Line Items]
Number of securities in unrealized loss position	39	33
Number of securities in unrealized loss position in for greater than twelve months	14	15
Number of securities in unrealized loss position in for less than twelve months	25	18
Mortgage-backed securities - residential
Schedule Of Available For Sale and Held To Maturity Securities [Line Items]
Number of securities in unrealized loss position in for greater than twelve months	9
Number of securities in unrealized loss position in for less than twelve months	9
State and political subdivisions
Schedule Of Available For Sale and Held To Maturity Securities [Line Items]
Number of securities in unrealized loss position in for greater than twelve months	5
Number of securities in unrealized loss position in for less than twelve months	16