CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Cash Flows [Abstract]
Net earnings	$ 214,891	$ 187,329	$ 145,461
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	99,995	96,008	100,810
(Gain) loss on sale of businesses	(875)	(845)	16,991
(Gain) loss on fixed asset disposals	29	(2,069)	(945)
Deferred income taxes	(5,782)	1,224	63,535
Share-based compensation	11,572	9,478	9,473
Impairment of assets			40,813
Change in operating assets and liabilities, net of businesses acquired and divested:
Accounts receivable, net	(16,388)	91,692	(77,106)
Inventories, net	19,711	4,391	(4,039)
Progress payments	(774)	2,583	3,680
Accounts payable and accrued expenses	4,323	4,125	(447)
Deferred revenue	36,898	(11,084)	4,839
Income taxes	(5,479)	11,797	(7,436)
Net pension and postretirement liabilities	3,481	3,405	(139,610)
Other Operating Activities, Cash Flow Statement		20,405
Increase (Decrease) in Other Noncurrent Liabilities	25,686	11,474	(5,410)
Other current and long-term assets and liabilities	1,424	(6,716)	11,870
Net cash provided by operating activities	388,712	423,197	162,479
Cash flows from investing activities:
Proceeds from sales and disposals of long-lived assets	6,769	3,674	2,277
Proceeds from divestiture	6,973	1,027	31,344
Additions to property, plant, and equipment	(52,705)	(46,776)	(35,512)
Acquisition of businesses, net of cash acquired	(232,630)	(295)	(13,228)
Additional consideration of prior period acquisitions	(735)	(564)	(457)
Net cash used for investing activities	(272,328)	(42,934)	(15,576)
Cash flows from financing activities:
Borrowings under revolving credit facility	7,658	7,839	70,324
Payment of revolving credit facilities	(8,176)	(8,430)	(70,134)
Principal payments on debt	(150,000)	0	(8,400)
Repurchases of common stock	(52,127)	(105,249)	(294,130)
Proceeds from share-based compensation	14,179	22,300	28,706
Dividends paid	(24,740)	(23,067)	(24,122)
Proceeds from (Payments for) Other Financing Activities	(692)	(635)	(581)
Excess tax benefits from share-based compensation	0	11,101	9,119
Net cash provided by financing activities	(213,898)	(96,141)	(289,218)
Effect of exchange-rate changes on cash	18,786	(18,971)	(19,104)
Net increase (decrease) in cash and cash equivalents	(78,728)	265,151	(161,419)
Cash and cash equivalents at beginning of period	553,848	288,697	450,116
Cash and cash equivalents at end of period	475,120	553,848	288,697
Supplemental disclosure of non-cash investing activities:
Capital Expenditures Incurred but Not yet Paid	$ 976	$ 2,512	$ 2,108