Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	9 Months Ended
	Sep. 24, 2011	Sep. 25, 2010
Cash flows provided by operating activities:
Net income	$ 48,274	$ 37,976
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	13,328	12,833
Impairment of long-lived assets	22
Loss on disposal of property, plant and equipment	117	35
Bad debt (recovery) expense	(60)	9
Stock-based compensation expense	4,751	2,388
Excess tax benefit from stock-based compensation arrangements	(2,542)	(2,500)
Deferred income taxes	221	1,037
Changes in operating assets and liabilities:
Accounts receivable	(10,710)	(8,423)
Inventories	(4,156)	(575)
Prepaid expenses and other assets	(3,395)	(306)
Accounts payable	5,577	(2,426)
Accrued expenses and other current liabilities	7,378	12,446
Other liabilities	(882)	1,030
Net cash provided by operating activities	57,923	53,524
Cash flows used in investing activities:
Purchases of property, plant and equipment	(12,290)	(10,024)
Proceeds from disposal of property, plant and equipment		20
Net cash used in investing activities	(12,290)	(10,004)
Cash flows used in financing activities:
Repurchase of Class A Common Stock	(50,871)	(51,908)
Proceeds from exercise of stock options	1,310	3,038
Excess tax benefit from stock-based compensation arrangements	2,542	2,500
Net proceeds from sale of investment shares	540	559
Net cash used in financing activities	(46,479)	(45,811)
Change in cash and cash equivalents	(846)	(2,291)
Cash and cash equivalents at beginning of period	48,969	55,481
Cash and cash equivalents at end of period	48,123	53,190
Supplemental disclosure of cash flow information:
Income taxes paid	$ 25,904	$ 16,887