Borrowed Funds Narrative Data (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Option advance borrowings from the FHLB	$ 30,496	$ 7,900
Secured customer repurchase agreement sweeps	$ 1,100	$ 1,600
FHLB borrowings interest rate, low range	0.00%	0.99%
FHLB borrowings interest rate, high range	4.31%	5.32%
FHLB borrowings weighted average interest rate	1.42%	3.46%
FHLB borrowing capacity, loans pledged	$ 162,300	$ 81,700
FHLB borrowing capacity, maximum available	91,500	49,500
FHLB borrowings and other credit subject to collateralization	31,700	9,100
FHLB borrowing capacity, unused and available	59,800	40,400
Correspondent banks line of credit, maximum available	12,000
Correspondent banks line of credit, amount outstanding	0	0
Securities pledged for customer repurchase agreement sweeps	1,800	2,400
Repurchase agreement sweeps, average daily balance	$ 1,600	$ 1,600
Repurchase agreement sweeps, weighted average interest rate for the year	0.26%	0.27%
Repurchase agreement sweeps, maximum borrowings outstanding during the year	$ 4,400	$ 3,800
Repurchase agreement sweeps, weighted average interest rate at year end	0.23%	0.25%