Incentive Plans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net impact to earnings	$ 95,762	$ 118,478	$ 98,589
Pension plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation expense	6,600	6,200	6,500
Profit Sharing Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation expense	$ 4,600	4,800	3,600
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Minimum | Pension plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer matching contribution, percent of match	50.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Maximum | Pension plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer matching contribution, percent of match	100.00%
Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Payout is scheduled to occur period no later than	90 days
Number of shares authorized (in shares)	860,629
Long Term Incentive Plan | Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash payments in connection with long term incentive plan	$ 4,500	3,100
Compensation expense	3,900	3,700	4,800
Net impact to earnings	2,700	2,600	3,400
Additional share based compensation expense expected to be recognized in next twelve months	1,200
Additional share based compensation expense expected to be recognized in two years	$ 300
Phantom Share Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Compensation expense	$ 8,600	6,600	5,400
Net impact to earnings	6,000	4,600	3,900
Compensation cost not yet recognized	$ 16,000
Cost not yet recognized, period for recognition	2 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 1,500	600	400
Net impact to earnings	1,000	$ 400	$ 300
Compensation cost not yet recognized	1,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	1,500
Net impact to earnings	$ 1,000