Retirement Plans and Postretirement Medical Benefits (Level 3 Gains and Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
United States | Private equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation
Fair value of plan assets - beginning of year	$ 91,500	$ 77,494
Realized gains	4,505	1,058
Unrealized gains (losses)	(18,386)	12,666
Net purchases, sales and settlements	(10,363)	282
Foreign currency changes	0	0
Fair value of plan assets - end of year	67,256	91,500
Foreign | Real estate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation
Fair value of plan assets - beginning of year	42,980	52,491
Realized gains	0	0
Unrealized gains (losses)	(3,951)	(6,741)
Net purchases, sales and settlements	2,014	1,729
Foreign currency changes	2,162	(4,499)
Fair value of plan assets - end of year	43,205	42,980
Foreign | Diversified growth funds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation
Fair value of plan assets - beginning of year	24,394	52,169
Realized gains	0	0
Unrealized gains (losses)	(3,133)	(5,933)
Net purchases, sales and settlements	(22,396)	(16,474)
Foreign currency changes	1,135	(5,368)
Fair value of plan assets - end of year	$ 0	$ 24,394