CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock	Noncontrolling interest in consolidated subsidiaries
Beginning balance at Dec. 31, 2016	$ 982,586	$ 27,900	$ 0	$ 1,874,722	$ (346,359)	$ (612,781)	$ 39,104
Increase (Decrease) in Shareholders' Equity
Net earnings	87,283			84,643			2,640
Other comprehensive income (loss)	39,902				40,560		(658)
Cash dividends declared	(16,939)			(16,939)			0
Dividends to noncontrolling interests	(2,889)						(2,889)
Stock plan exercises	(3,056)					(3,056)
Stock options exercised	10,168		(4,590)	3,448		11,310
Stock option expense	2,578		2,578
Stock awards	2,813		2,012			801
Ending balance at Jul. 01, 2017	1,102,446	27,900	0	1,945,874	(305,799)	(603,726)	38,197
Increase (Decrease) in Shareholders' Equity
Cumulative impact of ASC 606 adoption | Accounting Standards Update 2014-09	9,771			9,771
Cumulative impact of ASC 606 adoption | Accounting Standards Update 2016-16	1,038			1,038
Beginning balance at Dec. 30, 2017	1,151,795	27,900	0	1,954,344	(279,022)	(590,386)	38,959
Increase (Decrease) in Shareholders' Equity
Net earnings	75,160			72,241			2,919
Other comprehensive income (loss)	(29,202)				(32,144)		2,942
Cash dividends declared	(16,893)			(16,893)			0
Dividends to noncontrolling interests	(4,852)						(4,852)
Purchase of noncontrolling interests	5,510		0				5,510
Addition of noncontrolling interest	3,200						3,200
Purchase of treasury shares	(43,999)					(43,999)
Stock plan exercises	(1,769)					(1,769)
Stock options exercised	5,711		(4,459)	3,418		6,752
Stock option expense	2,151		2,151
Stock awards	3,223		2,308			915
Ending balance at Jun. 30, 2018	$ 1,149,824	$ 27,900	$ 0	$ 2,023,919	$ (311,166)	$ (628,487)	$ 37,658