Employee Benefit Plans (Schedule of Defined Benefit Plan Activity) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Amounts recognized in the consolidated balance sheets:
Prepaid pension costs	$ 44,585	$ 35,209
Non-current employee benefit liabilities	(68,970)	(66,616)
Pension Benefits
Change in benefit obligation:
Benefit obligation at January 1	(125,842)	(128,997)
Service cost	(415)	(592)	$ (533)
Interest cost	(2,284)	(3,545)	(4,860)
Plan settlement	0	7,255
Plan amendment	0	0
Benefits paid	6,452	7,008
Expenses paid	291	255
Actuarial gain (loss)	632	(7,226)
Benefit obligation at December 31	(121,166)	(125,842)	(128,997)
Change in plan assets:
Fair value of plan assets at January 1	102,812	101,051
Actual return on plan assets	8,373	8,919
Plan settlement	0	(7,255)
Expenses paid	(291)	(255)
Contributions	103	7,360
Benefits paid	(6,452)	(7,008)
Fair value of plan assets at December 31	104,545	102,812	101,051
Unfunded status at December 31	(16,621)	(23,030)
Amounts recognized in the consolidated balance sheets:
Prepaid pension costs	44,585	35,209
Other accrued liabilities	(95)	(100)
Non-current employee benefit liabilities	(61,111)	(58,139)
Net amounts recognized	(16,621)	(23,030)
Other Postretirement Benefits
Change in benefit obligation:
Benefit obligation at January 1	(9,101)	(8,986)
Service cost	0	0	(3)
Interest cost	(224)	(286)	(347)
Plan settlement	0	0
Plan amendment	(48)	0
Benefits paid	471	500
Expenses paid	0	0
Actuarial gain (loss)	422	(329)
Benefit obligation at December 31	(8,480)	(9,101)	(8,986)
Change in plan assets:
Fair value of plan assets at January 1	0	0
Actual return on plan assets	0	0
Plan settlement	0	0
Expenses paid	0	0
Contributions	471	500
Benefits paid	(471)	(500)
Fair value of plan assets at December 31	0	0	$ 0
Unfunded status at December 31	(8,480)	(9,101)
Amounts recognized in the consolidated balance sheets:
Prepaid pension costs	0	0
Other accrued liabilities	(621)	(624)
Non-current employee benefit liabilities	(7,859)	(8,477)
Net amounts recognized	$ (8,480)	$ (9,101)

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

Name:	us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.