Pension and Other Postretirement Employee Benefits (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Funding of pension and other postretirement benefit plans	$ 1,087,000	$ 1,296,000
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Change in participants pension benefits	0
Non-cash pretax settlement charge	$ 14,200,000
Qualified Plan [Member] | Pension Plans [Member] | Funded with Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Transfer of outstanding pension benefit obligation related to qualified pension plans to insurance company		75,600,000
Reduction in funded status of qualified pension plans		$ 6,200,000