Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 24, 2016	Sep. 30, 2017	Sep. 24, 2016
Income Statement [Abstract]
Operating revenues	$ 12,896	$ 15,968	$ 41,336	$ 44,622
Operating costs	11,275	12,087	35,471	37,215
Gross profit	1,621	3,881	5,865	7,407
Selling, general and administrative expenses	3,041	3,511	9,503	10,214
Operating income (loss)	(1,420)	370	(3,638)	(2,807)
Other income (expense):
Other income, net	2	10	57	17
Interest expense, net	(19)	(44)	(95)	(129)
Income (loss) from operations before income taxes	(1,437)	336	(3,676)	(2,919)
Provision (benefit) for federal and state income taxes	10,717	(153)	10,250	(1,056)
Net income (loss)	$ (12,154)	$ 489	$ (13,926)	$ (1,863)
Basic and diluted income (loss) per common share:	$ (0.44)	$ 0.02	$ (0.51)	$ (0.07)
Basic and diluted weighted average shares used in computing earnings (loss) per share:	27,446,000	27,700,000	27,257,000	27,823,000

The aggregate direct operating costs incurred during the reporting period.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The net amount of operating interest income (expense).

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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