Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 27, 2014	$ 89,779	$ 13,998	$ 77,745	$ (1,964)
Balance (in shares) at Dec. 27, 2014		13,998
Other comprehensive income (loss)	(1,214)			(1,214)
Net income	11,606		11,606
Expense of stock options and restricted stock units	719		719
Exercise of stock options	937	$ 156	781
Exercise of stock options (in shares)		156
Settlement of restricted stock units	0	$ 19	(19)
Settlement of restricted stock units (in shares)		19
Tax benefit from settlement of stock compensation	701		701
Tax withholding for equity awards	(79)		(79)
Dividends declared	(6,072)		(6,072)
Stock issued to directors as compensation	103	$ 7	96
Stock issued to directors as compensation (in shares)		7
Balance at Dec. 26, 2015	96,480	$ 14,180	85,478	(3,178)
Balance (in shares) at Dec. 26, 2015		14,180
Other comprehensive income (loss)	(1,102)			(1,102)
Net income	11,493		11,493
Expense of stock options and restricted stock units	398		398
Exercise of stock options	547	$ 96	451
Exercise of stock options (in shares)		96
Settlement of restricted stock units	0	$ 16	(16)
Settlement of restricted stock units (in shares)		16
Tax benefit from settlement of stock compensation	35		35
Dividends declared	(6,282)		(6,282)
Stock issued to directors as compensation	144	$ 13	131
Stock issued to directors as compensation (in shares)		13
Balance at Dec. 31, 2016	101,713	$ 14,305	91,688	(4,280)
Balance (in shares) at Dec. 31, 2016		14,305
Other comprehensive income (loss)	1,670			1,670
Net income	14,061		14,061
Expense of stock options and restricted stock units	522		522
Exercise of stock options	159	$ 28	131
Exercise of stock options (in shares)		28
Settlement of restricted stock units	0	$ 26	(26)
Settlement of restricted stock units (in shares)		26
Dividends declared	(6,607)		(6,607)
Stock issued to directors as compensation	152	$ 13	139
Stock issued to directors as compensation (in shares)		13
Balance at Dec. 30, 2017	$ 111,670	$ 14,372	$ 99,908	$ (2,610)
Balance (in shares) at Dec. 30, 2017		14,372