Employee Benefit Obligations - Asset Categories (Details)	Dec. 31, 2024	Dec. 31, 2023
U.S. | Minimum | Fixed income securities
Target asset allocations
Target asset allocations (as a percent)	40.00%
U.S. | Minimum | Equity securities
Target asset allocations
Target asset allocations (as a percent)	20.00%
U.S. | Minimum | Alternative investments
Target asset allocations
Target asset allocations (as a percent)	5.00%
U.S. | Maximum | Fixed income securities
Target asset allocations
Target asset allocations (as a percent)	70.00%
U.S. | Maximum | Equity securities
Target asset allocations
Target asset allocations (as a percent)	40.00%
U.S. | Maximum | Alternative investments
Target asset allocations
Target asset allocations (as a percent)	25.00%
UNITED KINGDOM | Minimum | Cash and cash equivalents
Target asset allocations
Target asset allocations (as a percent)	0.00%
UNITED KINGDOM | Minimum | Equity securities
Target asset allocations
Target asset allocations (as a percent)	0.00%
UNITED KINGDOM | Minimum | Insurance contract
Target asset allocations
Target asset allocations (as a percent)	90.00%
UNITED KINGDOM | Maximum | Cash and cash equivalents
Target asset allocations
Target asset allocations (as a percent)	10.00%
UNITED KINGDOM | Maximum | Equity securities
Target asset allocations
Target asset allocations (as a percent)	10.00%
UNITED KINGDOM | Maximum | Insurance contract
Target asset allocations
Target asset allocations (as a percent)	100.00%
Defined Benefit Pension Plans
Target asset allocations
Weighted average asset allocations (as a percent)	100.00%	100.00%
Defined Benefit Pension Plans | Cash and cash equivalents
Target asset allocations
Weighted average asset allocations (as a percent)	1.00%	1.00%
Defined Benefit Pension Plans | Fixed income securities
Target asset allocations
Weighted average asset allocations (as a percent)	24.00%	24.00%
Defined Benefit Pension Plans | Equity securities
Target asset allocations
Weighted average asset allocations (as a percent)	15.00%	13.00%
Defined Benefit Pension Plans | Insurance contract
Target asset allocations
Weighted average asset allocations (as a percent)	59.00%	61.00%
Defined Benefit Pension Plans | Alternative investments
Target asset allocations
Weighted average asset allocations (as a percent)	1.00%	1.00%