Note 8 - Earnings Per Share (Detail) - Computation of Basic and Diluted Earnings Per Share under the Two-class Method (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011
Net income as reported	$ 23,604	$ 25,269	$ 41,493	$ 46,847
Less: Distributed earnings available to participating securities	(6)	(2)	(11)	(5)
Less: Undistributed earnings available to participating securities	(31)	(103)	(81)	(155)
Numerator for basic earnings per share —
Undistributed and distributed earnings available to common shareholders	23,567	25,164	41,401	46,687
Add: Undistributed earnings allocated to participating securities	31	102	80	155
Less: Undistributed earnings reallocated to participating securities	(31)	(100)	(79)	(152)
Numerator for diluted earnings per share —
Undistributed and distributed earnings available to common shareholders	$ 23,567	$ 25,166	$ 41,402	$ 46,690
Denominator for basic earnings per share —
Weighted-average shares (in Shares)	21,778	22,191	21,693	22,034
Effect of dilutive securities:
Common stock equivalents (in Shares)	296	399	310	426
Denominator for diluted earnings per share —
Adjusted for weighted-average shares & assumed conversions (in Shares)	22,074	22,590	22,004	22,460
Basic earnings per share (in Dollars per share)	$ 1.08	$ 1.13	$ 1.91	$ 2.12
Diluted earnings per share (in Dollars per share)	$ 1.07	$ 1.11	$ 1.88	$ 2.08