Condensed Consolidated Statements Of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Condensed Consolidated Statements Of Comprehensive Loss [Abstract]
Net income (loss)	$ 6,718	$ 5,473	$ 2,794	$ (2,248)
Other comprehensive income (loss):
Change in fair value of derivatives, net of tax of nil, $227, nil and $41	(2,707)	(745)	(687)	(217)
Change in fair value of investment securities, net of tax of nil, $47, nil and $13	(13)	(134)	229	(37)
Other comprehensive loss	(2,720)	(879)	(458)	(254)
Comprehensive income (loss)	$ 3,998	$ 4,594	$ 2,336	$ (2,502)