Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement of Cash Flows [Abstract]
Cash, Including Discontinued Operations		$ 140,800	$ 136,089
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 24,154	140,800
Net (loss) earnings	(46,226)	43,676	(69,742)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	0	692
Cash flows from operating activities:
Net (loss) earnings	(46,226)	43,676	(70,434)
Adjustments to reconcile (loss) earnings from continuing operations, net of tax to net cash provided by operating activities:
Depreciation and amortization	40,712	36,654	43,899
Amortization of debt issuance costs	2,750	1,836	1,746
Accretion of convertible notes discount	0	2,957	2,860
Provision for doubtful accounts	1,301	575	1,381
Impairment of Long-Lived Assets to be Disposed of	0	0	36,285
Gain (Loss) on Disposition of Business, Non Cash	(457)	234	(493)
Net loss (gain) on sale of assets	136	(8)	200
Goodwill and Intangible Asset Impairment	25,306	0	50,307
Program inventory impairment	44,542	0	0
Program contract costs impairment	9,135	0	0
Net loss (gain) on derivative instruments	1,175	1,025	(466)
Stock compensation expense	7,821	6,687	4,979
Noncash Consideration on Sale of Aircraft	(827)	0	0
Deferred income taxes	(19,054)	20,998	(6,055)
Changes in assets and liabilities, excluding effects of acquisitions/divestitures:
Accounts receivable	(8,387)	78,367	7,042
Increase (Decrease) in Contract with Customer, Asset	(707)	(3,482)	12,629
increase (Decrease) in Capitalized Contract Cost	637	725	294
Inventories	(17,848)	(10,357)	(18,485)
Income tax refunds receivable	(144)	(8,565)	2,763
Increase (Decrease) in Operating Right of Use Assets	3,551	1,798	1,513
Other assets	(2,899)	3,450	2,490
Accounts payable - trade	1,959	(18,398)	(9,227)
Increase (Decrease) in Contract with Customer, Liability	4,433	(30,708)	(29,555)
Increase (Decrease) in Operating Lease Liabilities	(3,707)	(1,918)	(1,560)
Payments for Retention Plans	0	25,108	0
Other current liabilities	(2,860)	(8,880)	16,955
Income taxes payable	12	295	(4,885)
Pension liabilities	(17,745)	(37,580)	(21,550)
Other long-term liabilities	(1,640)	(5,575)	(6,164)
Net cash provided by operating activities	20,969	48,698	16,469
Cash flows from investing activities:
Proceeds from Divestiture of Businesses	0	0	5,223
Proceeds from Sales of Business, Affiliate and Productive Assets	1,200		493
Proceeds from Divestiture of Businesses, Net of Cash Divested		(3,428)
Expenditures for property, plant & equipment	(23,689)	(17,530)	(17,783)
Acquisition of businesses	(441,340)	0	(304,661)
Payments to Acquire Investments	(10,000)	0	0
Other, net	778	(154)	(1,994)
Net Cash Provided by (Used in) Investing Activities	(473,051)	(21,112)	(318,722)
Cash flows from financing activities:
Borrowings under revolving credit agreement	412,000	0	201,100
Proceeds from (Repayments of) Other Long-term Debt	(49,000)	0	(201,100)
Purchase of treasury shares	(801)	(618)	(14,210)
Dividends paid	(22,363)	(22,241)	(22,210)
Debt issuance costs	(4,380)	0	0
Other, net	467	626	2,885
Net cash provided by (used in) financing activities	335,923	(22,233)	(33,535)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	(116,159)	5,353	(335,788)
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations	(487)	(642)	337
Cash and cash equivalents and restricted cash at beginning of period (See Note 2)	140,800	136,089
Cash and cash equivalents and restricted cash at end of period (See Note 2)	$ 24,154	$ 140,800	$ 136,089