Acquisitions (Purchase Price Of Assets Acquired And Liabilities Assumed) (Details) (USD $) In Thousands	Jul. 31, 2011 Aegis Lightwave, Inc. [Member]	Dec. 31, 2010 Max Levy Autograph, Inc. [Member]
Business Acquisition [Line Items]
Short-term investment	$ 565
Accounts receivable, net	4,572	586
Inventories	2,853	275
Prepaid and other current assets	238	91
Deferred income taxes	9,976	171
Property, plant and equipment	2,900	2,845
Intangible assets	14,000	5,610
Goodwill	21,202	6,485
Total assets acquired	56,306	16,063
Accounts payable	1,375	154
Deferred income taxes	5,655	2,625
Long-term debt	1,295
Other accrued liabilities	1,840	471
Total liabilities assumed	10,165	3,250
Net assets acquired	$ 46,141	$ 12,813