CONSOLIDATED CONDENSED STATEMENTS OF EQUITY (Unaudited) (USD $) In Thousands, unless otherwise specified	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Earnings [Member]	Employee Stock Notes Receivable [Member]	Noncontrolling Interest [Member]	Total
Balance at Dec. 25, 2010	$ 19,333	$ 138,573	$ 414,108	$ 4,165	$ (1,670)	$ 6,667	$ 581,176
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings			6,223			866	7,089
Foreign currency translation adjustment				(321)		(272)	(593)
Purchase of additional noncontrolling interest						(402)	(402)
Capital contribution from noncontrolling interest						80	80
Distributions to noncontrolling interest						(1,213)	(1,213)
Cash dividends per share			(3,905)				(3,905)
Issuance of shares under employee stock plans	65	1,241					1,306
Issuance of shares under stock grant programs	154	1	7				162
Issuance of shares under deferred compensation plans	5	(5)					0
Tax benefits from non-qualified stock options exercised		240					240
Expense associated with share-based compensation arrangements		1,281					1,281
Accrued expense under deferred compensation plans		579					579
Note receivable adjustment	(1)	(61)			62		0
Payments received on employee stock notes receivable					169		169
Balance at Sep. 24, 2011	19,556	141,849	416,433	3,844	(1,439)	5,726	585,969
Balance at Dec. 31, 2011	19,624	143,988	410,848	3,600	(1,255)	5,794	582,599
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings			25,862			1,290	27,152
Foreign currency translation adjustment				954		384	1,338
Purchase of additional noncontrolling interest							0
Capital contribution from noncontrolling interest						436	436
Distributions to noncontrolling interest						(871)	(871)
Cash dividends per share			(3,946)				(3,946)
Issuance of shares under employee stock plans	82	1,744					1,826
Issuance of shares under stock grant programs	52	24	8				84
Issuance of shares under deferred compensation plans	33	(33)					0
Tax benefits from non-qualified stock options exercised		307					307
Expense associated with share-based compensation arrangements		993					993
Accrued expense under deferred compensation plans		1,582					1,582
Notes receivable written-off	(1)	(24)			25		0
Payments received on employee stock notes receivable					217		217
Balance at Sep. 29, 2012	$ 19,790	$ 148,581	$ 432,772	$ 4,554	$ (1,013)	$ 7,033	$ 611,717