Quarterly Financial Data Quarterly Financial Data (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 25, 2016	Sep. 25, 2016	Jun. 26, 2016	Mar. 27, 2016	Dec. 27, 2015	Sep. 27, 2015	Jun. 28, 2015	Mar. 29, 2015	Dec. 31, 2016	Dec. 25, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information [Abstract]
Net sales	$ 188,323,000	$ 175,580,000	$ 182,709,000	$ 186,065,000	$ 194,621,000	$ 175,656,000	$ 183,940,000	$ 173,729,000	$ 732,677,000	$ 732,677,000	$ 727,946,000	$ 745,447,000
Gross profit	17,968,000	10,981,000	29,540,000	27,715,000	23,591,000	16,484,000	19,920,000	11,222,000	86,204,000	86,204,000	71,217,000	50,222,000
Income from operations	11,090,000	5,250,000	19,540,000	18,722,000	13,527,000	8,059,000	11,039,000	3,669,000	54,602,000	54,602,000	36,294,000	17,913,000
Income before income taxes	11,542,000	4,910,000	19,247,000	19,022,000	13,362,000	7,615,000	10,734,000	3,572,000	54,721,000	54,721,000	35,283,000	15,702,000
Income tax provision	3,764,000	(1,064,000)	6,082,000	4,558,000	5,232,000	(2,669,000)	(4,200,000)	(762,000)	13,340,000	(13,340,000)	(11,339,000)	(6,899,000)
Net Income	$ 7,778,000	$ 5,974,000	$ 13,165,000	$ 14,464,000	$ 8,130,000	$ 4,946,000	$ 6,534,000	$ 4,334,000	$ 41,381,000	$ 41,381,000	$ 23,944,000	$ 8,803,000
Basic	$ 0.31	$ 0.24	$ 0.52	$ 0.56	$ 0.31	$ 0.19	$ 0.24	$ 0.16	$ 1.63	$ 1.63	$ 0.90	$ 0.33
Diluted	0.31	0.23	0.52	0.56	0.31	0.19	0.24	0.16	1.62	$ 1.62	0.90	$ 0.33
Dividends declared per share	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.72		$ 0.72