Consolidated Statement of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Capital in Excess of Par Value	Retained Earnings	Treasury Stock	Deferred Compensation Obligation	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Balance — (in shares) at Dec. 31, 2017		176,793			46,471,000
Balance — at Dec. 31, 2017	$ 1,670,954	$ 220,991	$ 488,326	$ 3,503,947	$ (2,059,558)	$ 6,354	$ (505,473)	$ 16,367
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock activity under stock plans (in shares)					198,000
Stock activity under stock plans	(1,894)		(10,432)		$ 8,538
Stock-based compensation	3,961		3,961
Net earnings	16,459			15,143				1,316
Cash dividends declared	(24,809)			(24,809)
Other comprehensive income (loss), net of tax	19,167						18,362	805
Purchase of shares from and dividends paid to noncontrolling interests	(169)							(169)
Other, net	(138)					(138)
Balance — (in shares) at Mar. 31, 2018		176,793.000			46,273,000
Balance — at Mar. 31, 2018	$ 1,703,546	$ 220,991	481,855	3,514,296	$ (2,051,020)	6,216	(487,111)	18,319
Balance — (in shares) at Dec. 31, 2018	176,793,000	176,793			46,237,000
Balance — at Dec. 31, 2018	$ 1,660,780	$ 220,991	494,551	3,543,007	$ (2,049,404)	7,117	(573,947)	18,465
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock activity under stock plans (in shares)					268,000
Stock activity under stock plans	(2,670)		(14,488)		$ 11,818
Stock-based compensation	7,610		7,610
Net earnings	59,496			57,261				2,235
Cash dividends declared	(25,254)			(25,254)
Other comprehensive income (loss), net of tax	8,224						7,547	677
Purchase of shares from and dividends paid to noncontrolling interests	(190)							(190)
Other, net	$ (10)					(10)
Balance — (in shares) at Mar. 31, 2019	176,793,000	176,793.000			45,969,000
Balance — at Mar. 31, 2019	$ 1,707,986	$ 220,991	$ 487,673	$ 3,575,014	$ (2,037,586)	$ 7,107	$ (566,400)	$ 21,187