Components of Net Periodic Benefit Cost (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Retirement Benefits [Abstract]
Years of employment benefits are based upon			5 years
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined contribution plan, employer contribution amount	$ 0	$ 10,000,000	$ 0	$ 10,000,000
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1,146,000	1,267,000	3,544,000	5,199,000
Interest cost	3,028,000	2,724,000	8,609,000	6,786,000
Expected return on plan assets	(7,905,000)	(7,072,000)	(22,865,000)	(22,190,000)
Amortization of Prior service cost	0	0	0	0
Amortization of Net loss (gain)	398,000	660,000	397,000	660,000
Net periodic (income) benefit cost	(3,333,000)	(2,421,000)	(10,315,000)	(9,545,000)
Pension Plan | Acquired RSI Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	0	0	0	0
Interest cost	76,000	75,000	229,000	125,000
Expected return on plan assets	(121,000)	(111,000)	(365,000)	(185,000)
Amortization of Prior service cost	0	0
Amortization of Net loss (gain)			0	0
Net periodic (income) benefit cost	(45,000)	(36,000)	(136,000)	(60,000)
RIM Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	69,000	93,000	207,000	279,000
Interest cost	158,000	97,000	474,000	291,000
Expected return on plan assets	0	0	0	0
Amortization of Prior service cost	0	0	0	0
Amortization of Net loss (gain)	14,000	111,000	42,000	333,000
Net periodic (income) benefit cost	241,000	301,000	723,000	903,000
Post-retirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	54,000	87,000	161,000	261,000
Interest cost	242,000	150,000	727,000	450,000
Expected return on plan assets	0	0	0	0
Amortization of Prior service cost	0	0	0	0
Amortization of Net loss (gain)	0	78,000	0	234,000
Net periodic (income) benefit cost	296,000	315,000	888,000	945,000
Post-retirement Plan | Acquired RSI Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	17,000	35,000	51,000	58,000
Interest cost	26,000	35,000	80,000	58,000
Expected return on plan assets	0	0	0	0
Amortization of Prior service cost	(15,000)	0
Amortization of Net loss (gain)			(46,000)	0
Net periodic (income) benefit cost	28,000	70,000	85,000	116,000
Split-Dollar Life Insurance
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	69,000	130,000	208,000	383,000
Interest cost	204,000	158,000	613,000	453,000
Expected return on plan assets	0	0	0	0
Amortization of Prior service cost	14,000	14,000	42,000	42,000
Amortization of Net loss (gain)	0	151,000	0	453,000
Net periodic (income) benefit cost	$ 287,000	$ 453,000	$ 863,000	$ 1,331,000