Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 29, 2012	Oct. 01, 2011
Cash Provided by (Used in) Operating Activities:
Net Income	$ 7,238	$ 6,369
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation	3,813	4,035
Amortization	554	567
Amortization of deferred gain	(391)	(391)
Provision for bad debts	(177)	104
Deferred income taxes	(320)	1,105
Provision for accrued warranty costs	161	592
Warranty costs paid	(205)	(572)
Stock-based compensation and directors' fees	1,076	1,432
Excess tax benefit from stock-based awards	(644)	(839)
Unrealized (gain) loss on short-term investments	(10)	118
Unrealized loss (gain) on foreign exchange contracts	137	(601)
Unrealized foreign currency transaction gain	(71)	(93)
Changes in operating assets and liabilities:
Accounts receivable	337	(54)
Inventories	(2,668)	(9,160)
Other assets	895	(1,008)
Accounts payable	(1,727)	(1,442)
Other liabilities	(3,846)	(3,487)
Net Cash Provided by (Used in) Operating Activities	4,152	(3,325)
Cash Used in Investing Activities:
Purchases of short-term investments	(23,042)	(18,059)
Sales of short-term investments	22,826	20,088
Additions to property, plant and equipment	(4,203)	(3,180)
Additions to trademarks and patents	(265)	(126)
Net Cash Used in Investing Activities	(4,684)	(1,277)
Cash (Used in) Provided by Financing Activities:
Borrowing on long-term debt	3,000	16,300
Repayment of long-term debt	(7,221)	(14,300)
Excess tax benefit from stock-based awards	644	839
Proceeds from sale of Class A common stock, net	320	(247)
Purchase of treasury stock	(2,198)	(1,619)
Net Cash (Used in) Provided by Financing Activities	(5,455)	973
Effect of exchange rate changes on cash and cash equivalents	595	163
Decrease in Cash and Cash Equivalents	(5,392)	(3,466)
Cash and cash equivalents at beginning of period	25,991	16,650
Cash and Cash Equivalents at End of Period	20,599	13,184
SUPPLEMENTAL INFORMATION
Income taxes paid, net	1,490	661
Interest paid	$ 371	$ 526

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.