CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jul. 01, 2012	Jul. 03, 2011
Operating Activities:
Consolidated net income	$ 38,847	$ 33,846
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	25,501	29,179
Payments relating to restructuring activities	(826)	(1,756)
Pension plan funding	(7,852)	(1,106)
Tax benefits related to stock incentive programs	154	407
Other non-cash items	3,997	3,271
Net changes in operating assets and liabilities	4,985	(7,150)
Net cash provided by operating activities	64,806	56,691
Investing Activities:
Purchases of property, plant and equipment	(23,834)	(21,943)
Proceeds from sale of short-term investments	1,494	5,251
Purchases of short-term investments	(3,074)	(4,336)
Net cash used in investing activities	(25,414)	(21,028)
Financing Activities:
Proceeds from issuance of long-term debt	0	1,596
Repayment of long-term debt	(280)	0
Net issuance (repayment) of short-term debt	(1,597)	320
Purchase of common shares for treasury	(5,504)	(23,292)
Proceeds from issuance of stock under option plan	2,354	4,821
Excess tax benefits related to stock incentive programs	0	153
Dividends paid to non-controlling interest	(3,249)	0
Cash dividends paid	(1,775)	(1,823)
Net cash used in financing activities	(10,051)	(18,225)
Effect of exchange rate changes on cash and cash equivalents	(3,034)	10,841
Net increase in cash and cash equivalents	26,307	28,279
Cash and cash equivalents at beginning of period	395,152	367,827
Cash and cash equivalents at end of period	421,459	396,106
Supplemental disclosure of cash flow information:
Interest paid	1,737	1,634
Income taxes paid	14,092	15,832
Non-cash financing activities:
Treasury stock purchases settled after period-end	$ 474	$ 345