CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net income (loss)	$ (143,176)	$ 16,645
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation	66,067	64,904
Amortization	17,067	17,783
Deferred income tax (benefit) expense	(10,396)	(6,407)
Equity (income) loss of unconsolidated entities, net	245	195
Dividends from unconsolidated entities	526	0
(Gain) loss on early extinguishment of debt	(2,254)	2,668
Goodwill impairment charge	104,580	0
Other, net	1,020	(2,149)
Changes in assets and liabilities, net of acquisitions and dispositions of businesses:
Accounts receivable	87,607	(23,484)
Increase (Decrease) in Income Taxes Receivable	7,687	0
Inventories	(8,435)	15,456
Contract assets	7,836	(37,866)
Right-of-use assets	14,383	13,897
Accounts payable	18,847	(13,491)
Accrued interest payable	(740)	(137)
Accrued compensation	(5,884)	4,701
Advances on contracts	(13,626)	(13,351)
Operating lease liabilities	(14,095)	(13,506)
Retirement plan liabilities, net	(21,587)	(27,858)
Other assets and liabilities	12,067	15,530
Net cash provided by operating activities	117,739	13,530
Cash flows from investing activities:
Purchases of property, plant and equipment	(61,791)	(68,646)
Proceeds from sales of assets	6,591	10,042
Expenditures for intangible assets	(100)	(132)
Proceeds from notes receivable	8,605	6,400
Net proceeds (payments) from settlement of foreign currency forward exchange contracts	4,999	(978)
Payments for settlements of interest rate swaps	2,123	0
Other investing activities, net	153	133
Net cash used by investing activities	(43,666)	(53,181)
Cash flows from financing activities:
Short-term borrowings, net	(31)	4,444
Current maturities and long-term debt:
Additions	104,961	465,518
Reductions	(152,861)	(413,481)
Dividends paid to noncontrolling interests	0	(3,094)
Noncontrolling Interest - purchase or sale	1,901	0
Stock-based compensation - Employee taxes paid	(1,698)	(3,172)
Payment of contingent consideration	(6,915)	0
Deferred financing costs	0	(7,828)
Other financing activities, net	0	(601)
Net cash (used) provided by financing activities	(54,643)	41,786
Effect of exchange rate changes on cash and cash equivalents, including restricted cash	(5,751)	483
Net increase in cash and cash equivalents, including restricted cash	13,679	2,618
Cash and cash equivalents, including restricted cash, at beginning of period	87,128	79,669
Cash and cash equivalents, including restricted cash, at end of period	100,807	82,287
Supplemental Cash Flow Information [Abstract]
Change in accrual for purchases of property, plant and equipment included in accounts payable	$ 6,836	$ 2,158