CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS AND RETAINED EARNINGS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 28, 2013		Sep. 29, 2012		Sep. 28, 2013		Sep. 29, 2012
CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS AND RETAINED EARNINGS
Net product sales	$ 191,807		$ 200,274		$ 404,074		$ 418,193
Rental and royalty revenue	902		908		2,807		2,948
Total revenue	192,709		201,182		406,881		421,141
Product cost of goods sold	125,833		135,852		264,974		283,615
Rental and royalty cost	223		232		698		739
Total costs	126,056		136,084		265,672		284,354
Product gross margin	65,974		64,422		139,100		134,578
Rental and royalty gross margin	679		676		2,109		2,209
Total gross margin	66,653		65,098		141,209		136,787
Selling, marketing and administrative expenses	33,166		32,685		87,620		84,946
Earnings from operations	33,487		32,413		53,589		51,841
Other income, net	3,105		1,537		7,401		4,428
Earnings before income taxes	36,592		33,950		60,990		56,269
Provision for income taxes	10,549		11,027		17,509		17,061
Net earnings	26,043		22,923		43,481		39,208
Net earnings per share (in dollars per share)	$ 0.44		$ 0.38		$ 0.73		$ 0.65
Dividends per share (in dollars per share)	$ 0.08	[1]	$ 0.08	[1]	$ 0.24	[1]	$ 0.24	[1]
Average number of shares outstanding (in shares)	59,579		60,456		59,723		60,634
Retained earnings at beginning of period	39,199		82,931		80,210		114,269
Net earnings	26,043		22,923		43,481		39,208
Cash dividends	(4,764)		(4,683)		(14,185)		(13,972)
Stock dividends					49,028		38,334
Retained earnings at end of period	$ 60,478		$ 101,171		$ 60,478		$ 101,171

[1] Does not include 3% stock dividend to shareholders of record on 3/5/13 and 3/6/12.