Investment Securities - Summary of Unrealized Losses of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Securities with losses under 12 months, Fair Value	$ 6,544	$ 19,360
Held-to-maturity, Securities with losses under 12 months, Gross Unrealized Loss	19	208
Held-to-maturity, Securities with losses over 12 months, Fair Value	19,645	33,635
Held-to-maturity, Securities with losses over 12 months, Gross Unrealized Loss	351	800
Held-to-maturity, Total, Fair Value	26,189	52,995
Held-to-maturity, Total, Gross Unrealized Loss	370	1,008
Obligations of state and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Securities with losses under 12 months, Fair Value	6,544	11,761
Held-to-maturity, Securities with losses under 12 months, Gross Unrealized Loss	19	35
Held-to-maturity, Securities with losses over 12 months, Fair Value	1,302	13,263
Held-to-maturity, Securities with losses over 12 months, Gross Unrealized Loss	19	157
Held-to-maturity, Total, Fair Value	7,846	25,024
Held-to-maturity, Total, Gross Unrealized Loss	38	192
GSE mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Securities with losses under 12 months, Fair Value	0	0
Held-to-maturity, Securities with losses under 12 months, Gross Unrealized Loss	0	0
Held-to-maturity, Securities with losses over 12 months, Fair Value	7,309	8,142
Held-to-maturity, Securities with losses over 12 months, Gross Unrealized Loss	82	164
Held-to-maturity, Total, Fair Value	7,309	8,142
Held-to-maturity, Total, Gross Unrealized Loss	82	164
Collateralized mortgage obligations: residential
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Securities with losses under 12 months, Fair Value	0	0
Held-to-maturity, Securities with losses under 12 months, Gross Unrealized Loss	0	0
Held-to-maturity, Securities with losses over 12 months, Fair Value	11,034	12,230
Held-to-maturity, Securities with losses over 12 months, Gross Unrealized Loss	250	479
Held-to-maturity, Total, Fair Value	11,034	12,230
Held-to-maturity, Total, Gross Unrealized Loss	$ 250	479
Collateralized mortgage obligations: commercial
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Securities with losses under 12 months, Fair Value		7,599
Held-to-maturity, Securities with losses under 12 months, Gross Unrealized Loss		173
Held-to-maturity, Securities with losses over 12 months, Fair Value		0
Held-to-maturity, Securities with losses over 12 months, Gross Unrealized Loss		0
Held-to-maturity, Total, Fair Value		7,599
Held-to-maturity, Total, Gross Unrealized Loss		$ 173