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Employee Benefits - Additional Information (Details) - USD ($) | 1 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Apr. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022
Warrick Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Actuarial loss due to decrease in discount rate | $ 600,000 |  |
Expected to amortize on a straight-line basis, years | 10 years |  |
Projected benefit obligation increased due to remeasurement | $ 7,200,000 |  |
Increase in pre-tax prior service cost | $ 6,600,000 |  |
Benefit obligation, discount rate | 4.99% |  | 5.26%
Expected long-term rate of return on plan assets | $ 0 |  |
Description of assumption used to determine benefit obligation |  | The discount rate assumption used to determine the benefit obligation in the April 30, 2023 remeasurement was 4.99% compared to 5.26% at December 31, 2022. There was no change in the April 30, 2023 remeasurement to expected long-term rate of return on plan assets assumption or expected contributions compared to December 31, 2022. |
Accrued salaries, wages and related expenses |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Accrued salaries, wages and related expenses |  | $ 7,500,000 |
Level 1 | Fair Value, Measurements, Recurring |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of deferred compensation assets |  | $ 10,600,000 | $ 9,800,000

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