Components of Net Periodic Benefit Cost (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 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	$ 0	$ 0	$ 0
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1,199,000	1,966,000	2,398,000	3,932,000
Interest cost	2,790,000	2,031,000	5,581,000	4,062,000
Expected return on plan assets	(7,480,000)	(7,559,000)	(14,960,000)	(15,118,000)
Amortization of Prior service cost	0	0	0	0
Amortization of Net loss (gain)	0	0	0	0
Net periodic (income) benefit cost	(3,491,000)	(3,562,000)	(6,981,000)	(7,124,000)
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	50,000	152,000	50,000
Expected return on plan assets	(122,000)	(74,000)	(243,000)	(74,000)
Amortization of Net loss (gain)	0	0	0	0
Net periodic (income) benefit cost	(46,000)	(24,000)	(91,000)	(24,000)
RIM Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	69,000	93,000	138,000	186,000
Interest cost	158,000	97,000	316,000	194,000
Expected return on plan assets	0	0	0	0
Amortization of Prior service cost	14,000	0	28,000	0
Amortization of Net loss (gain)	0	111,000	0	222,000
Net periodic (income) benefit cost	241,000	301,000	482,000	602,000
Post-retirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	54,000	87,000	108,000	174,000
Interest cost	242,000	150,000	485,000	300,000
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	156,000
Net periodic (income) benefit cost	296,000	315,000	593,000	630,000
Post-retirement Plan | Acquired RSI Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	17,000	23,000	34,000	23,000
Interest cost	27,000	23,000	53,000	23,000
Expected return on plan assets	0	0	0	0
Amortization of Net loss (gain)	(15,000)	0	(30,000)	0
Net periodic (income) benefit cost	29,000	46,000	57,000	46,000
Split-Dollar Life Insurance
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	69,000	128,000	139,000	253,000
Interest cost	204,000	153,000	409,000	295,000
Expected return on plan assets	0	0	0	0
Amortization of Prior service cost	14,000	14,000	28,000	28,000
Amortization of Net loss (gain)	0	151,000	0	302,000
Net periodic (income) benefit cost	$ 287,000	$ 446,000	$ 576,000	$ 878,000