Postretirement Benefits - Actuarial Assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Actuarial assumptions used to determine benefit obligations:
Discount rate	5.34%	5.67%
Employee Pension Plan
Actuarial assumptions used to determine benefit obligations:
Discount rate	5.34%	5.67%
Rate of compensation increase	3.25%	3.21%
Actuarial assumptions used to determine net periodic benefit costs:
Discount rate	5.67%	3.16%	2.96%
Expected return on assets	6.50%	5.50%	5.50%
Rate of compensation increase	3.30%	3.21%	3.21%
Supplemental Employee Retirement Plan (SERP)
Actuarial assumptions used to determine benefit obligations:
Discount rate	5.11%	5.46%
Rate of compensation increase	5.00%	5.00%
Actuarial assumptions used to determine net periodic benefit costs:
Discount rate	5.46%	3.11%	2.86%
Rate of compensation increase	5.00%	5.00%	5.00%