Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
Current Assets:
Cash and cash equivalents	$ 76,402	$ 49,524	$ 74,463	$ 49,450
Accounts receivable, net of allowance for doubtful accounts of $144 and $160 as of December 27, 2014 and December 28, 2013, respectively	36,860	42,001
Inventories	51,307	56,397
Prepaid expenses and other current assets	12,887	9,606
Income tax receivable	21,321	1,038
Deferred income taxes	8,685	5,712
Total current assets	207,462	164,278
Property, plant and equipment, net	381,569	266,558
Other assets	12,447	9,556
Goodwill	3,683	3,683
Total assets	605,161	444,075
Current Liabilities:
Accounts payable	35,576	34,424
Current portion of debt and capital lease obligations	55	53
Accrued expenses and other current liabilities	74,539	69,900
Total current liabilities	110,170	104,377
Deferred income taxes	50,717	32,394
Debt and capital lease obligations, less current portion	528	584
Other liabilities	7,606	4,635
Total liabilities	169,021	141,990
Commitments and Contingencies
Stockholders' Equity:
Additional paid-in capital	224,909	173,025
Accumulated other comprehensive loss, net of tax	(1,133)	(417)	(883)	(838)
Retained earnings	212,233	129,349
Total stockholders' equity	436,140	302,085	245,091	184,745
Total liabilities and stockholders' equity	605,161	444,075
Common Class A | Common Stock
Stockholders' Equity:
Common Stock	95	88
Total stockholders' equity	95	88	87	87
Common Class B | Common Stock
Stockholders' Equity:
Common Stock	36	40
Total stockholders' equity	$ 36	$ 40	$ 41	$ 41