Components of Accumulated Other Comprehensive Loss (Details 2) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Revenues		$ 2,069,225	$ 1,889,065	$ 1,848,399
Interest expense		(103,872)	(75,156)	(63,235)
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax				(25,863)
Total costs and expenses		1,958,211	1,946,408	1,760,023
Income from continuing operations before income taxes		(18,550)	(122,958)	37,506
Income Tax Expense (Benefit)		28,185	10,381	9,089
Income (loss) from discontinued businesses	$ 5,100
Net income (loss)		88,098	176,431	$ (2,729)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Pension and Other Postretirement Benefits Cost (Reversal of Cost)		18,917	17,792
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Total costs and expenses		19,394	18,389
Income Tax Expense (Benefit)		(1,170)	(1,218)
Net income (loss)		18,224	17,171
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Pension and Other Postretirement Benefits Cost (Reversal of Cost)		519	534
Reclassification out of Accumulated Other Comprehensive Income [Member] | Settlement/curtailment gain
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Pension and Other Postretirement Benefits Cost (Reversal of Cost)		(42)	(33)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Settlement/curtailment gain | Discontinued Operations
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Pension and Other Postretirement Benefits Cost (Reversal of Cost)		0	96
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income Tax Expense (Benefit)		247	(960)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Foreign Currency Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income (loss) from discontinued businesses		(507)	0
Net income (loss)		(507)	0
Reclassification out of Accumulated Other Comprehensive Income [Member] | Foreign currency exchange forward contracts | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Revenues		1,638	(1,746)
Income from continuing operations before income taxes		(938)	2,499
Net income (loss)		(691)	1,539
Reclassification out of Accumulated Other Comprehensive Income [Member] | Interest rate swaps | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense		$ 2,576	$ (4,245)