Securities - Held-to-Maturity Securities Held by Company (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 140,579	$ 139,216
Gross Unrealized Gains	20	1,196
Gross Unrealized Losses	1,222	97
Fair Value	139,377	140,315
Obligations of U.S. Government sponsored entities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	131,306	131,707
Gross Unrealized Gains	0	1,103
Gross Unrealized Losses	1,198	90
Fair Value	130,108	132,720
Obligations of U.S. states and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	9,273	7,509
Gross Unrealized Gains	20	93
Gross Unrealized Losses	24	7
Fair Value	$ 9,269	$ 7,595