Components of Net Periodic Benefit Costs (Tables)

6 Months Ended

Jun. 30, 2022

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

Net periodic benefit (income) cost for Pension Plan, RIM Plan, Post-retirement Plan and Split-Dollar Life Insurance plan benefits for the three and six months ended June 30, 2022 and 2021, includes the following components:

	For the Three Months Ended June 30,
	Pension Plan				RIM Plan				Post-retirement Plan				Split-Dollar Life Insurance
	2022		2021		2022		2021		2022		2021		2022		2021		Affected Line Item in the Consolidated Statements of Income
	(In thousands)
Service cost	$	1,966	$	2,150	$	93	$	100	$	110	$	130	$	128	$	141	Compensation and employee benefits
Interest cost	2,081		1,756		97		86		173		141		153		125		Other non-interest expense
Expected return on plan assets	(7,633)		(6,318)		—		—		—		—		—		—		Other non-interest expense
Amortization:
Prior service cost	—		—		—		—		—		—		14		14		Other non-interest expense
Net loss	—		1,000		111		166		78		153		151		191		Other non-interest expense
Net periodic (income) benefit cost	$	(3,586)	$	(1,412)	$	301	$	352	$	361	$	424	$	446	$	471

13.    Components of Net Periodic Benefit Cost (continued)

	For the Six Months Ended June 30,
	Pension Plan				RIM Plan				Post-retirement Plan				Split-Dollar Life Insurance
	2022		2021		2022		2021		2022		2021		2022		2021		Affected Line Item in the Consolidated Statements of Income
	(In thousands)
Service cost	$	3,932	$	4,300	$	186	$	200	$	197	$	260	$	253	$	282	Compensation and employee benefits
Interest cost	4,112		3,512		194		172		323		282		295		250		Other non-interest expense
Expected return on plan assets	(15,192)		(12,636)		—		—		—		—		—		—		Other non-interest expense
Amortization:
Prior service cost	—		—		—		—		—		—		28		28		Other non-interest expense
Net loss	—		2,000		222		332		156		306		302		382		Other non-interest expense
Net periodic (income) benefit cost	$	(7,148)	$	(2,824)	$	602	$	704	$	676	$	848	$	878	$	942