Benefit Plans - Defined Benefit Plans - Components of Pension Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Supplemental Retirement Plan
Components of net periodic benefit cost:
Service cost	$ 263	$ 249
Interest cost	1,059	947
Amortization of net actuarial loss	184	292
Accelerated benefits for Presidio SERP agreements due to change in control	1,465
Net periodic benefit cost	2,971	1,488
Amount recognized in other comprehensive income	2,847	1,577
Split-Dollar Life Insurance Benefit Plan
Components of net periodic benefit cost:
Interest cost	278	227
Amortization of prior transition obligation	(96)	(65)
Net periodic benefit cost	182	162
Amount recognized in other comprehensive income	$ 1,113	$ (30)