Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 355	$ 387	$ 1,065	$ 1,161
Interest cost	914	848	2,741	2,544
Expected return on assets	(1,508)	(1,621)	(4,523)	(4,863)
Net loss amortization	457	378	1,370	1,134
Prior service (credit) cost amortization	(3)	(3)	(10)	(10)
Net periodic benefit cost (income)	215	(11)	643	(34)
Defined Benefit Pension Plan Acquired
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	43	41	127	123
Expected return on assets	(74)	(73)	(220)	(218)
Net loss amortization	0	0	0	0
Prior service (credit) cost amortization	0	0	0	0
Net periodic benefit cost (income)	(31)	(32)	(93)	(95)
Restoration Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	84	73	254	220
Interest cost	178	149	534	447
Expected return on assets	0	0	0	0
Net loss amortization	139	169	419	508
Prior service (credit) cost amortization	2	2	5	5
Net periodic benefit cost (income)	$ 403	$ 393	$ 1,212	$ 1,180