Consolidated Statements Of Changes In Equity (USD $) In Thousands, except Share data	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock At Cost [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Non-Controlling Interest [Member]	Total
Beginning Balance at Dec. 27, 2008	$ 661	$ 154,533	$ 704,331	$ (605,828)	$ (561)	$ 0	$ 253,136
Beginning Balance, shares at Dec. 27, 2008	66,109,547			14,424,887
Net income (loss)			70,395			(445)	69,950
Dividends paid			(8,686)				(8,686)
Purchases of common stock				(55,757)			(55,757)
Purchases of common stock (shares)				1,624,547
Exercises of stock options and issuance and vesting of non-vested stock, including shortfall tax effect	2	1,899					1,901
Exercises of stock options and issuance and vesting of non-vested stock, including shortfall tax effect (shares)	145,811
Capital contribution from noncontrolling interest						580	580
Consideration for acquisition paid in common stock		(139)		1,139			1,000
Consideration for acquisition paid in common stock (shares)				(27,323)
Stock-based compensation		4,968					4,968
Foreign currency translation					547		547
Unrealized gain on available-for-sale investments, net of income taxes					512		512
Ending Balance at Dec. 26, 2009	663	161,261	766,040	(660,446)	498	135	268,151
Ending Balance, shares at Dec. 26, 2009	66,255,358			16,022,111
Net income (loss)			87,514			(932)	86,582
Dividends paid			(9,422)				(9,422)
Purchases of common stock				(102,736)			(102,736)
Purchases of common stock (shares)				2,652,791
Exercises of stock options and issuance and vesting of non-vested stock, including shortfall tax effect	2	3,238					3,240
Exercises of stock options and issuance and vesting of non-vested stock, including shortfall tax effect (shares)	279,811
Stock-based compensation		4,769					4,769
Foreign currency translation					182		182
Unrealized gain on available-for-sale investments, net of income taxes					201		201
Ending Balance at Dec. 25, 2010	665	169,268	844,132	(763,182)	881	(797)	250,967
Ending Balance, shares at Dec. 25, 2010	66,535,169			18,674,902
Net income (loss)			113,007			(62)	112,945
Dividends paid			(9,983)				(9,983)
Purchases of common stock				(50,450)			(50,450)
Purchases of common stock (shares)				1,206,111			1,206,111
Purchase of noncontrolling interest		(8,859)				859	(8,000)
Exercises of stock options and issuance and vesting of non-vested stock, including shortfall tax effect	1	291		(52)			240
Exercises of stock options and issuance and vesting of non-vested stock, including shortfall tax effect (shares)	67,317			1,276
Stock-based compensation		5,012					5,012
Foreign currency translation					(171)		(171)
Unrealized gain on available-for-sale investments, net of income taxes					17		17
Ending Balance at Dec. 31, 2011	$ 666	$ 165,712	$ 947,156	$ (813,684)	$ 727		$ 300,577
Ending Balance, shares at Dec. 31, 2011	66,602,486			19,882,289