Securities - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Securities Pledged
Amortized cost of securities	$ 87.7	$ 97.3
Fair value of pledged securities	88.0	97.1
Repurchase Agreements
Securities Pledged
Amortized cost of securities pledged	13.6	14.9
Securities pledged and available to be sold under repurchase agreements, fair value	13.7	15.0
Derivative
Securities Pledged
Amortized cost of securities pledged	3.1	2.8
Securities pledged and available to be sold under repurchase agreements, fair value	$ 3.2	$ 2.9