Basis of presentation and summary of significant accounting policies.

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Number of restaurants damaged by fire.

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Number of suppliers.

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Percentage of operating loss carry forwards tax savings payable to pre initial public offering stockholders.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The net amount (to the extent disclosed within this portion of the income statement) by which an insurance settlement exceeds incremental costs incurred from the event causing an interruption of business, plus the insurance award for earnings lost from the event, such as a natural catastrophe, explosion or fire.

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The expense in the period incurred with respect to protection provided by insurance entities against risks other than risks associated with production (which are allocated to cost of sales).

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Represents the number of restaurants.

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Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

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Cash received as payments for insurance premiums during the current period.

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The description of the nature of any restrictions on the ability of consolidated and unconsolidated subsidiaries to transfer funds to the parent in the form of cash dividends, loans and advances.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail)		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 30, 2014	Nov. 30, 2015 Restaurants	Jun. 29, 2016 USD ($) Restaurants	Jul. 01, 2015 USD ($)	Jun. 29, 2016 USD ($) Segment Restaurants Supplier	Jul. 01, 2015 USD ($)	Dec. 30, 2015 USD ($) Supplier	Jun. 30, 2016 USD ($) Restaurants	Dec. 31, 2014 USD ($)
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| Segment					1
Restricted dividend payments, description					Under the 2014 Revolver, Holdings may not make certain payments such as cash dividends, except that it may, inter alia, (i) pay up to $1 million per year to repurchase or redeem qualified equity interests of Holdings held by past or present officers, directors, or employees (or their estates) of the Company upon death, disability, or termination of employment, (ii) pay under its income tax receivable agreement (the “TRA”), and, (iii) so long as no default or event of default has occurred and is continuing, (a) make non-cash repurchases of equity interests in connection with the exercise of stock options by directors and officers, provided that those equity interests represent a portion of the consideration of the exercise price of those stock options, (b) pay up to $2.5 million per year pursuant to stock option plans, employment agreements, or incentive plans, (c) make up to $5 million in other restricted payments per year, and (d) make other restricted payments, provided that such payments would not cause, in each case, on a pro forma basis, (x) its lease-adjusted consolidated leverage ratio to equal or exceed 4.25 times and (y) its consolidated fixed charge coverage ratio to be less than 1.75 times.
Total amount of outstanding debt			$ 117,100,000		$ 117,100,000
Cash available			9,496,000	$ 6,414,000	9,496,000	$ 6,414,000	$ 6,101,000		$ 11,499,000
Number of restaurants damaged \| Restaurants		1
Costs incurred directly related to fire					48,000
Disposition of assets related to fire			87,000		87,000		111,000
Gain on recovery of insurance proceeds			600,000		889,000
Amount received from insurance company in cash					1,000,000
Unrecognized tax benefits, accrual of interest or penalties			0		0		$ 0
Unrecognized tax benefits, interest or penalties expenses			0	$ 0	0	$ 0
Percentage of cash savings in taxes realized as a result of utilizing net operating losses payable to pre-IPO stockholders	85.00%
Indefinite-lived Intangible Assets [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Asset impairment charges			$ 0		$ 0
Supplier Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of suppliers \| Supplier					0		2
Supplier Two [Member] \| Accounts Payable [Member] \| Supplier Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration							12.00%
Supplier Three [Member] \| Accounts Payable [Member] \| Supplier Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration							11.00%
Largest Supplier One [Member] \| Purchased [Member] \| Supplier Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration			34.00%	37.00%	34.00%	37.00%
The Greater Los Angeles Area [Member] \| Revenue [Member] \| Geographic Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration			75.00%	79.00%	75.00%	79.00%
Subsequent Event [Member] \| Parent [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| Restaurants								1
Senior Secured Revolving Credit Facility [Member] \| Subsequent Event [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Pre-payment for new restaurant								$ 3,000,000
2013 First Lien Credit Agreement [Member] \| Senior Secured Revolving Credit Facility [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Amount of borrowings available			$ 76,300,000		$ 76,300,000
Entity Operated Units [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| Restaurants			188		188
Franchised Units [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| Restaurants			251		251