Investment Securities - Portfolio of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	$ 103,412	$ 116,792
Gross Unrealized Gains	2,673	1,404
Gross Unrealized Losses	76	498
Fair Value	106,009	117,698
Obligations of state and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	40,695	43,737
Gross Unrealized Gains	1,151	697
Gross Unrealized Losses	0	6
Fair Value	41,846	44,428
GSE mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	47,451	55,696
Gross Unrealized Gains	1,496	705
Gross Unrealized Losses	0	131
Fair Value	48,947	56,270
Collateralized mortgage obligations: residential
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	9,414	10,803
Gross Unrealized Gains	0	0
Gross Unrealized Losses	76	361
Fair Value	9,338	10,442
Collateralized mortgage obligations: commercial
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	5,852	6,556
Gross Unrealized Gains	26	2
Gross Unrealized Losses	0	0
Fair Value	$ 5,878	$ 6,558