Securities - Additional Information (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($) security item	Dec. 31, 2017 USD ($)
Additional Information
The number of holdings of securities of any one issuer other than the U.S. Government and its sponsored entities | security	0
Holdings of securities as percentage of shareholders' equity, considered as threshold for disclosure purpose	10.00%
Number of securities held | security	498
Number of available for sale securities held | item	172
Number of held to maturity securities held | item	326
Number of securities with fair values below amortized cost | item	393
Total unrealized loss for securities 12 months or more | $	$ 11,963
12 Months or More | $	136,665	$ 149,999
Municipals - exempt from Federal tax
Additional Information
12 Months or More | $	$ 19,076	$ 19,240