Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 28, 2013	$ 87,955	$ 13,657	$ 69,379	$ 4,919
Balance (in shares) at Dec. 28, 2013		13,657
Other comprehensive loss	(6,883)			(6,883)
Net income	11,817		11,817
Expense of stock options	716		716
Exercise of stock options	1,386	$ 301	1,085
Exercise of stock options (in shares)		301
Settlement of restricted stock units	0	$ 34	(34)
Settlement of restricted stock units (in shares)		34
Dividends declared	(5,294)		(5,294)
Stock issued to directors as compensation	82	$ 6	76
Stock issued to directors as compensation (in shares)		6
Balance at Dec. 27, 2014	89,779	$ 13,998	77,745	(1,964)
Balance (in shares) at Dec. 27, 2014		13,998
Other comprehensive loss	(1,214)			(1,214)
Net income	11,606		11,606
Expense of stock options	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 loss	(1,102)			(1,102)
Net income	11,493		11,493
Expense of stock options	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