Postretirement Benefits - Schedule of Pension Assets by Component at Fair Value (Details) - Pension Plan - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 592,072	$ 570,767
Percentage of plan assets	100.00%	100.00%
Investment funds, percentage ownership by pension plan	1.00%
Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 565,095	$ 552,453
Percentage of plan assets	95.00%	97.00%
Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 341,075	$ 341,570
Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	224,020	210,883
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 26,977	$ 18,314
Percentage of plan assets	5.00%	3.00%
Exchange traded fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 35,996	$ 18,715
Percentage of total plan assets, within plan asset category	6.00%	3.00%
Investment grade securities issued term	10 years
Exchange traded fund | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 35,996	$ 18,715
Exchange traded fund | Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Exchange traded fund | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Equity Exchange Traded Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 295,168	$ 315,886
Percentage of total plan assets, within plan asset category	50.00%	55.00%
Equity Exchange Traded Fund | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 295,168	$ 315,886
Equity Exchange Traded Fund | Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Equity Exchange Traded Fund | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
U.S. Government and Agency
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 180,280	$ 167,450
Percentage of total plan assets, within plan asset category	30.00%	30.00%
U.S. Government and Agency | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 0	$ 0
U.S. Government and Agency | Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	180,280	167,450
U.S. Government and Agency | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Other bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 4	$ 5
Percentage of total plan assets, within plan asset category	0.00%	0.00%
Other bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 0	$ 0
Other bonds | Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	4	5
Other bonds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Guaranteed annuity contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 43,736	$ 43,428
Percentage of total plan assets, within plan asset category	7.00%	8.00%
Guaranteed annuity contract | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 0	$ 0
Guaranteed annuity contract | Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	43,736	43,428
Guaranteed annuity contract | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Short-term investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 8,808	$ 6,506
Percentage of total plan assets, within plan asset category	2.00%	1.00%
Short-term investments | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 8,808	$ 6,506
Short-term investments | Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Short-term investments | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 1,103	$ 463
Percentage of total plan assets, within plan asset category	0.00%	0.00%
Other | Quoted Prices in Active Markets for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 1,103	$ 463
Other | Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	0	0
Other | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, within plan asset category	$ 0	$ 0