Guarantees (Changes in Accrued Warranty) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2012	Sep. 24, 2011	Sep. 29, 2012		Sep. 24, 2011
Balance at beginning of period	$ 6,134	$ 6,080	$ 6,801	[1]	$ 5,016
Warranty expense accruals	1,006	2,587	3,819		8,036
Warranty payments	(1,540)	(2,383)	(5,020)		(6,768)
Balance at end of period	$ 5,600	$ 6,284	$ 5,600		$ 6,284

[1] Derived from December 31, 2011 audited financial statements.