Securities - Fair Value and Gross Unrealized Losses by Investment Category and Length of Time (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value
Total	$ 144,802	$ 197,475
Less than 12 Months	83,056	195,789
12 Months or More	61,746	1,686
Unrealized Loss
Total	2,282	4,130
Less than 12 Months	466	4,103
12 Months or More	1,816	27
Federal agencies and GSEs
Fair Value
Total	73,901	89,597
Less than 12 Months	32,812	89,597
12 Months or More	41,089	0
Unrealized Loss
Total	1,511	2,387
Less than 12 Months	131	2,387
12 Months or More	1,380	0
Mortgage-backed and CMOs
Fair Value
Total	56,190	57,762
Less than 12 Months	42,328	56,076
12 Months or More	13,862	1,686
Unrealized Loss
Total	542	938
Less than 12 Months	270	911
12 Months or More	272	27
State and municipal
Fair Value
Total	13,165	47,221
Less than 12 Months	6,370	47,221
12 Months or More	6,795	0
Unrealized Loss
Total	225	782
Less than 12 Months	61	782
12 Months or More	164	0
Corporate
Fair Value
Total	1,546	2,895
Less than 12 Months	1,546	2,895
12 Months or More	0	0
Unrealized Loss
Total	4	23
Less than 12 Months	4	23
12 Months or More	$ 0	$ 0