Investment Securities - Portfolio of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	$ 87,462	$ 98,211
Gross Unrealized Gains	1,298	735
Gross Unrealized Losses	300	685
Fair Value	88,460	98,261
Obligations of state and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	36,482	40,515
Gross Unrealized Gains	724	309
Gross Unrealized Losses	0	39
Fair Value	37,206	40,785
GSE mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	39,817	44,375
Gross Unrealized Gains	569	426
Gross Unrealized Losses	82	311
Fair Value	40,304	44,490
Collateralized mortgage obligations: residential
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	8,240	8,969
Gross Unrealized Gains	0	0
Gross Unrealized Losses	218	323
Fair Value	8,022	8,646
Collateralized mortgage obligations: commercial
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	2,923	4,352
Gross Unrealized Gains	5	0
Gross Unrealized Losses	0	12
Fair Value	$ 2,928	$ 4,340