Employee Benefit Plans - Assumptions used (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Pension | Retirement Income Plan
Weighted-average assumptions used to determine obligations (balance sheet):
Discount rate	5.02%	2.49%	2.10%
Weighted-average assumptions used to determine net periodic benefit cost (statement of operations):
Discount rate	2.49%	2.10%	3.00%
Expected return on plan assets	6.50%	6.00%	6.50%
Pension | National Service-Related Pension Plan (NSRPP)
Weighted-average assumptions used to determine obligations (balance sheet):
Discount rate	5.11%	2.77%	2.49%
Weighted-average assumptions used to determine net periodic benefit cost (statement of operations):
Discount rate	2.77%	2.49%	3.25%
Expected return on plan assets	6.50%	6.00%	6.50%
Pension | Superannuation
Weighted-average assumptions used to determine obligations (balance sheet):
Discount rate	5.40%	2.55%	1.50%
Rate of compensation increase	2.50%	2.50%	3.25%
Weighted-average assumptions used to determine net periodic benefit cost (statement of operations):
Discount rate	2.55%	1.50%	2.30%
Expected return on plan assets	5.00%	5.00%	5.00%
Rate of compensation increase	2.50%	3.25%	3.25%
Pension | Austria Plans
Weighted-average assumptions used to determine obligations (balance sheet):
Discount rate	3.78%	0.94%
Rate of compensation increase	3.00%	2.50%
Weighted-average assumptions used to determine net periodic benefit cost (statement of operations):
Discount rate	0.94%	0.75%
Other Post-Retirement Benefits (OPRB)
Weighted-average assumptions used to determine obligations (balance sheet):
Discount rate	4.81%	1.95%	1.41%
Weighted-average assumptions used to determine net periodic benefit cost (statement of operations):
Discount rate	1.95%	1.41%	2.55%