Postretirement Benefits - Asset Allocation (Details) - Employee Pension Plan	Dec. 31, 2024	Dec. 31, 2023
Target asset allocation for the portfolio:
Total plan assets	100.00%	100.00%
Actual asset allocation for the portfolio:
Total plan assets	100.00%	100.00%
Total equity securities
Target asset allocation for the portfolio:
Total plan assets	35.00%	45.00%
Actual asset allocation for the portfolio:
Total plan assets	35.00%	45.00%
U.S. equity securities
Target asset allocation for the portfolio:
Total plan assets	21.00%	27.00%
Actual asset allocation for the portfolio:
Total plan assets	21.00%	26.00%
U.S. small capitalization core equity
Target asset allocation for the portfolio:
Total plan assets	100.00%
Non-U.S. equity securities
Target asset allocation for the portfolio:
Total plan assets	14.00%	18.00%
Actual asset allocation for the portfolio:
Total plan assets	14.00%	19.00%
International small capitalization risk controlled equity
Target asset allocation for the portfolio:
Total plan assets	11.00%
International emerging markets equity
Target asset allocation for the portfolio:
Total plan assets	20.00%
International risk controlled equity
Target asset allocation for the portfolio:
Total plan assets	69.00%
Debt securities
Target asset allocation for the portfolio:
Total plan assets	64.00%	54.00%
Actual asset allocation for the portfolio:
Total plan assets	63.00%	54.00%
U.S. Treasury Strips
Target asset allocation for the portfolio:
Total plan assets	59.00%
U.S. corporate bonds with an emphasis on long duration bonds rated A or better
Target asset allocation for the portfolio:
Total plan assets	41.00%
Other
Target asset allocation for the portfolio:
Total plan assets	1.00%	1.00%
Actual asset allocation for the portfolio:
Total plan assets	2.00%	1.00%