Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 24, 2011
Operating activities:
Net earnings	$ 64,381,000	$ 54,118,000	$ 55,063,000
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation of fixed assets	28,801,000	26,175,000	25,046,000
Amortization of intangibles and deferred costs	4,751,000	4,762,000	5,188,000
Losses (gains) from disposals and impairment of property & equipment	126,000	(146,000)	52,000
Share-based compensation	1,870,000	1,246,000	918,000
Gain on bargain purchase of a business			(6,580,000)
Deferred income taxes	68,000	3,771,000	6,117,000
Changes in assets and liabilities, net of effects from purchase of companies:
Increase in accounts receivable, net	(11,148,000)	(605,000)	(5,231,000)
Increase in inventories	(1,819,000)	(6,463,000)	(6,262,000)
(Increase) decrease in prepaid expenses and other	(1,067,000)	1,982,000	1,870,000
Increase in accounts payable and accrued liabilities	579,000	5,248,000	4,284,000
Net cash provided by operating activities	86,548,000	89,425,000	80,456,000
Investing activities:
Payments for purchases of companies, net of cash acquired		(7,900,000)	(8,806,000)
Purchases of property, plant and equipment	(35,821,000)	(42,800,000)	(29,124,000)
Purchases of marketable securities	(111,241,000)	(68,450,000)	(63,293,000)
Proceeds from redemption and sales of marketable securities	25,307,000	109,744,000	37,568,000
Proceeds from disposal of property and equipment	1,199,000	1,038,000	394,000
Other	(281,000)	(950,000)	(644,000)
Net cash used in investing activities	(120,837,000)	(9,318,000)	(63,905,000)
Financing activities:
Payments to repurchase common stock	(14,500,215)	(8,167,125)
Proceeds from issuance of common stock	3,948,000	4,228,000	5,377,000
Payments on capitalized lease obligations	(340,000)	(312,000)	(244,000)
Payment of cash dividend	(11,468,000)	(9,549,000)	(8,540,000)
Net cash used in financing activities	(22,360,000)	(13,800,000)	(3,407,000)
Effect of exchange rates on cash and cash equivalents	(204,000)	412,000	(330,000)
Net (decrease) increase in cash and cash equivalents	(56,853,000)	66,719,000	12,814,000
Cash and cash equivalents at beginning of year	154,198,000	87,479,000	74,665,000
Cash and cash equivalents at end of year	97,345,000	154,198,000	87,479,000
Excluding Noncash Effect [Member]
Adjustments to reconcile net earnings to net cash provided by operating activities:
Deferred income taxes	$ 74,000	$ 3,108,000	$ 6,108,000