Shake Shack (SHAK) 10-K 26 Feb 18 2017 Q4 Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($)	12 Months Ended
	Dec. 27, 2017	Feb. 14, 2018	Jun. 28, 2017
Document Information [Line Items]
Document type	10-K
Amendment flag	false
Document period end date	Dec. 27, 2017
Document fiscal year focus	2,017
Document fiscal period focus	Q4
Entity registrant name	Shake Shack Inc.
Entity central index key	1,620,533
Current fiscal year end date	--12-27
Entity filer category	Large Accelerated Filer
Entity current reporting status	Yes
Entity Public Float			$ 778,146,403
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Class A Common Stock
Document Information [Line Items]
Entity common stock, shares outstanding (in shares)		27,078,149
Class B Common Stock
Document Information [Line Items]
Entity common stock, shares outstanding (in shares)		9,701,815

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Current assets:
Cash and cash equivalents	$ 21,507	$ 11,607
Marketable securities	63,036	62,040
Accounts receivable	5,641	6,006
Inventories	1,258	806
Prepaid expenses and other current assets	1,757	3,485
Total current assets	93,199	83,944
Property and equipment, net	187,095	136,264
Deferred income taxes, net	185,914	313,207
Other assets	4,398	4,779
TOTAL ASSETS	470,606	538,194
Current liabilities:
Accounts payable	8,210	6,921
Accrued expenses	11,649	8,538
Accrued wages and related liabilities	6,228	6,084
Other current liabilities	7,937	10,173
Total current liabilities	34,024	31,716
Deemed landlord financing	14,518	2,007
Deferred rent	36,596	31,107
Liabilities under tax receivable agreement, net of current portion	158,436	267,902
Other long-term liabilities	2,553	4,109
Total liabilities	246,127	336,841
Commitments and contingencies
Stockholders' equity:
Preferred stock, no par value—10,000,000 shares authorized; none issued and outstanding as of December 27, 2017 and December 28, 2016, respectively.	0	0
Additional paid-in capital	153,105	135,448
Retained earnings	16,399	16,719
Accumulated other comprehensive loss	(49)	(15)
Total stockholders' equity attributable to Shake Shack Inc. / members' equity	169,492	152,188
Non-controlling interests	54,987	49,165
Total equity	224,479	201,353
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	470,606	538,194
Class A common stock, $0.001 par value—200,000,000 shares authorized; 26,527,477 and 25,151,384 shares issued and outstanding as of December 27, 2017 and December 28, 2016, respectively.
Stockholders' equity:
Common stock	27	25
Class B common stock, $0.001 par value—35,000,000 shares authorized; 10,250,007 and 11,253,592 shares issued and outstanding as of December 27, 2017 and December 28, 2016, respectively.
Stockholders' equity:
Common stock	$ 10	$ 11

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 27, 2017	Dec. 28, 2016	Feb. 04, 2015
Preferred stock, par value (in dollars per share)	$ 0	$ 0
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Class A Common Stock
Common stock par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000	200,000,000
Common stock, shares, issued (in shares)	26,527,477	25,151,384
Common stock, shares, outstanding (in shares)	26,527,477	25,151,384
Class B Common Stock
Common stock par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	35,000,000	35,000,000	35,000,000
Common stock, shares, issued (in shares)	10,250,007	11,253,592
Common stock, shares, outstanding (in shares)	10,250,007	11,253,592

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Income Statement [Abstract]
Shack sales	$ 346,388	$ 259,350	$ 183,219
Licensing revenue	12,422	9,125	7,373
TOTAL REVENUE	358,810	268,475	190,592
Shack-level operating expenses:
Food and paper costs	98,337	73,752	54,079
Labor and related expenses	91,740	65,540	44,752
Other operating expenses	35,805	24,946	16,307
Occupancy and related expenses	28,197	21,820	15,207
General and administrative expenses	39,003	30,556	37,825
Depreciation expense	21,704	14,502	10,222
Pre-opening costs	9,603	9,520	5,430
Loss on disposal of property and equipment	608	34	17
TOTAL EXPENSES	324,997	240,670	183,839
OPERATING INCOME	33,813	27,805	6,753
Other income, net	128,123	1,065	7
Interest expense	(1,643)	(374)	(332)
INCOME BEFORE INCOME TAXES	160,293	28,496	6,428
Income tax expense	151,409	6,350	3,304
NET INCOME	8,884	22,146	3,124
Less: net income attributable to non-controlling interests	9,204	9,700	11,900
Net income (loss) attributable to Shake Shack Inc.	$ (320)	$ 12,446	$ (8,776)
Earnings (loss) per share of Class A common stock
Basic (in dollars per share)	$ (0.01)	$ 0.54	$ (0.65)
Diluted (in dollars per share)	$ (0.01)	$ 0.53	$ (0.65)
Weighted-average shares of Class A common stock outstanding
Basic (shares)	25,876	22,956	13,588
Diluted (shares)	25,876	23,449	13,588

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands		12 Months Ended
		Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income		$ 8,884	$ 22,146	$ 3,124
Available-for-sale securities:
Change in net unrealized holding (losses)	[1]	(94)	(35)	(11)
Less: reclassification adjustments for net realized losses included in net income	[1]	47	19	0
Net change	[1]	(47)	(16)	(11)
OTHER COMPREHENSIVE LOSS, NET OF TAX		(47)	(16)	(11)
COMPREHENSIVE INCOME		8,837	22,130	3,113
Less: comprehensive income attributable to non-controlling interests		9,191	9,694	11,894
COMPREHENSIVE INCOME ATTRIBUTABLE TO SHAKE SHACK INC.		$ (354)	$ 12,436	$ (8,781)
[1]	Net of tax benefit of $0 for fiscal years ended December 27, 2017, December 28, 2016 and December 30, 2015.

CONSOLIDATED STATEMENTS OF COM6

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Parenthetical) - USD ($)	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Statement of Comprehensive Income [Abstract]
Comprehensive income net of tax benefit	$ 0	$ 0	$ 0

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' AND MEMBERS' EQUITY - USD ($) $ in Thousands	Total	Class A Common Stock	Class B Common Stock	Members' Equity	Common stockClass A Common Stock	Common stockClass B Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Non- Controlling Interest	Secondary Offering and Redemption of Units	Secondary Offering and Redemption of UnitsCommon stockClass A Common Stock	Secondary Offering and Redemption of UnitsCommon stockClass B Common Stock	Secondary Offering and Redemption of UnitsAdditional Paid-In Capital	Secondary Offering and Redemption of UnitsNon- Controlling Interest	USC Merger	USC MergerCommon stockClass A Common Stock	USC MergerCommon stockClass B Common Stock	USC MergerAdditional Paid-In Capital	USC MergerNon- Controlling Interest
Beginning balance at Dec. 31, 2014	$ 12,600			$ 12,600	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Beginning balance (in shares) at Dec. 31, 2014					0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss prior to the Organizational Transactions	(13,049)			(13,049)
Other comprehensive loss:
Net unrealized losses related to available-for-sale securities	(11)								(5)	(6)
Member distributions	(11,125)			(11,125)
Equity-based compensation recognized prior to the Organizational Transactions	7,731			7,731
Issuance of Class A common stock sold in initial public offering, net of underwriting discounts, commissions and offering costs (in shares)					5,750,000
Issuance of Class A common stock sold in initial public offering, net of underwriting discounts, commissions and offering costs	109,262				$ 6		109,256
Issuance of class A common stock in settlement of unit appreciation rights (in shares)					339,306
Issuance of Class A common stock in settlement of unit appreciation rights	0						987			(987)
Effect of the Organizational Transactions	30			3,843	$ 6	$ 24	(75,182)			71,339
Effect of the Organizational Transactions (in shares)					5,968,841	24,191,853
Net income subsequent to the Organizational Transactions	16,173							4,273		11,900
Equity-based compensation	4,314						4,314
Establishment of liabilities under tax receivable agreement and related changes to deferred tax assets associated with increases in tax basis	31,094						31,094
Redemptions (in shares)												(6,003,308)	(6,003,308)				(1,727,804)	(1,727,804)
Redemptions											$ 0	$ 6	$ (6)	$ 19,934	$ (19,934)	$ 0	$ 2	$ (2)	$ 5,908	$ (5,908)
Net income	3,124
Ending balance at Dec. 30, 2015	157,019			0	$ 20	$ 16	96,311	4,273	(5)	56,404
Ending balance (in shares) at Dec. 30, 2015					19,789,259	16,460,741
Other comprehensive loss:
Net unrealized losses related to available-for-sale securities	(16)								(10)	(6)
Equity-based compensation	5,493						5,493
Establishment of liabilities under tax receivable agreement and related changes to deferred tax assets associated with increases in tax basis	15,833						15,833
Redemptions (in shares)					(5,207,149)							(5,207,149)	(5,207,149)
Redemptions											0	$ 5	$ (5)	16,986	$ (16,986)
Net income	22,146							12,446		9,700
Stock option exercises (in shares)					154,976
Stock option exercises	3,197				$ 0		795			2,402
Income tax effect of stock compensation plans	33						30			3
Distributions paid and payable to non-controlling interest holders	(2,352)									(2,352)
Ending balance at Dec. 28, 2016	201,353			0	$ 25	$ 11	135,448	16,719	(15)	49,165
Ending balance (in shares) at Dec. 28, 2016		25,151,384	11,253,592		25,151,384	11,253,592
Other comprehensive loss:
Net unrealized losses related to available-for-sale securities	(47)								(34)	(13)
Member distributions	0
Equity-based compensation	5,732						5,732
Establishment of liabilities under tax receivable agreement and related changes to deferred tax assets associated with increases in tax basis	3,059						3,059
Redemptions (in shares)					(1,003,585)							(1,003,585)	(1,003,585)
Redemptions										(4,415)	$ 0	$ 1	$ (1)	$ 4,415
Net income	8,884							(320)		9,204
Stock option exercises (in shares)					372,508
Stock option exercises	7,270				$ 1		4,451			2,818
Distributions paid and payable to non-controlling interest holders	(1,772)									(1,772)
Ending balance at Dec. 27, 2017	$ 224,479			$ 0	$ 27	$ 10	$ 153,105	$ 16,399	$ (49)	$ 54,987
Ending balance (in shares) at Dec. 27, 2017		26,527,477	10,250,007		26,527,477	10,250,007

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
OPERATING ACTIVITIES
Net income (loss) (including amounts attributable to non-controlling interests)	$ 8,884,000	$ 22,146,000	$ 3,124,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation expense	21,704,000	14,502,000	10,222,000
Equity-based compensation	5,623,000	5,354,000	16,681,000
Deferred income taxes	146,334,000	(523,000)	(734,000)
Non-cash interest expense	317,000	304,000	273,000
Excess tax benefits on equity-based compensation	0	(33,000)	0
Loss on sale of marketable securities	5,000	18,000	0
Loss on disposal of property and equipment	608,000	34,000	17,000
Other non-cash income	(127,221,000)	(688,000)	0
Changes in operating assets and liabilities:
Accounts receivable	6,421,000	2,974,000	775,000
Inventories	(452,000)	(263,000)	(14,000)
Prepaid expenses and other current assets	2,244,000	(756,000)	(958,000)
Other assets	(446,000)	(822,000)	1,293,000
Accounts payable	1,235,000	839,000	201,000
Accrued expenses	4,388,000	5,560,000	2,548,000
Accrued wages and related liabilities	144,000	280,000	3,394,000
Other current liabilities	(988,000)	2,130,000	257,000
Deferred rent	1,008,000	3,415,000	4,363,000
Other long-term liabilities	1,070,000	(186,000)	(184,000)
NET CASH PROVIDED BY OPERATING ACTIVITIES	70,878,000	54,285,000	41,258,000
INVESTING ACTIVITIES
Purchases of property and equipment	(61,533,000)	(54,433,000)	(32,117,000)
Purchases of marketable securities	(7,861,000)	(61,266,000)	(2,397,000)
Sales of marketable securities	7,451,000	938,000	0
NET CASH USED IN INVESTING ACTIVITIES	(61,943,000)	(114,761,000)	(34,514,000)
FINANCING ACTIVITIES
Payments on promissory note	0	(313,000)	0
Proceeds from Revolving Credit Facility	0	0	4,000,000
Payments on Revolving Credit Facility	0	0	(36,000,000)
Proceeds from deemed landlord financing	1,183,000	65,000	0
Payments on deemed landlord financing	(266,000)	0	0
Deferred financing costs	0	0	(103,000)
Proceeds from issuance of Class A common stock sold in initial public offering, net of underwriting discounts, commissions and offering costs	0	0	109,262,000
Proceeds from issuance of Class B common stock	0	0	30,000
Distributions paid to non-controlling interest holders	(2,379,000)	(1,745,000)	0
Distributions paid to members prior to the initial public offering	0	0	(11,125,000)
Payments under tax receivable agreement	(4,844,000)	0	0
Proceeds from stock option exercises	7,585,000	3,194,000	0
Employee withholding taxes related to net settled equity awards	(314,000)	0	(4,636,000)
Excess tax benefits from equity-based compensation	0	33,000	0
NET CASH PROVIDED BY FINANCING ACTIVITIES	965,000	1,234,000	61,428,000
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	9,900,000	(59,242,000)	68,172,000
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	11,607,000	70,849,000	2,677,000
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 21,507,000	$ 11,607,000	$ 70,849,000

NATURE OF OPERATIONS

NATURE OF OPERATIONS	12 Months Ended
	Dec. 27, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
NATURE OF OPERATIONS	NATURE OF OPERATIONS Sha ke Shack Inc. was formed on September 23, 2014 as a Delaware corporation for the purpose of facilitating an initial public offering and other related tran sactions in order to carry on the business of SSE Holdings, LLC and its subsidiaries. Unless the context otherwise requires, references to "we," "us," "our," "Shake Shack" and the "Company" refer to Shake Shack Inc. and its subsidiaries, including SSE Holdings, LLC, which we refer to as "SSE Holdings." We operate and license Shake Shack restaurants ("Shacks"), which serve hamburgers, hot dogs, chicken, crinkle cut fries, shakes, frozen custard, beer, wine and more. As of December 27, 2017 , there were 159 Shacks in operation, system-wide, of which 90 were domestic company-operated Shacks, 10 were domestic licensed Shacks and 59 were international licensed Shacks. Initial Public Offering On February 4, 2015, we completed an initial public offering ("IPO") of 5,750,000 shares of our Class A common stock at a public offering price of $21.00 per share, which includes 750,000 shares issued pursuant to the underwriters' over-allotment option. We received $112,298 in proceeds, net of underwriting discounts and commissions, which we used to purchase newly-issued membership interests from SSE Holdings at a price per interest equal to the initial public offering price of our Class A common stock. Organizational Transactions In connection with the IPO, we completed the following transactions (the "Organizational Transactions"): ▪ We amended and restated the limited liability company agreement of SSE Holdings (as amended, the "SSE Holdings LLC Agreement") to, among other things, (i) provide for a new single class of common membership interests in SSE Holdings ("LLC Interests"), (ii) exchange all of the membership interests of the then-existing holders of SSE Holdings for LLC Interests and (iii) appoint Shake Shack Inc. as the sole managing member of SSE Holdings. See Note 11 . ▪ We amended and restated our certificate of incorporation to, among other things, (i) provide for Class B common stock with voting rights but no economic interests (where "economic interests" means the right to receive any distributions or dividends, whether cash or stock, in connection with common stock) and (ii) issue shares of Class B common stock to the then-existing holders of SSE Holdings on a one -to-one basis with the number of LLC Interests they own. See Note 11 . ▪ We acquired, by merger, two entities that were owned by former indirect members of SSE Holdings, for which we issued 5,968,841 shares of Class A common stock as merger consideration (the "Mergers"). The only assets held by the two merged entities prior to the merger were 5,968,841 LLC Interests and a corresponding number of shares of Class B common stock. Upon consummation of the Mergers, we canceled the 5,968,841 shares of Class B common stock and recognized the 5,968,841 of LLC Interests at carrying value, as the Mergers are considered to be transactions between entities under common control. Following the completion of the Organizational Transactions, we owned 33.3% of SSE Holdings. The non-controlling interest holders subsequent to the Merger owned the remaining 66.7% of SSE Holdings. As a result of the Organizational Transactions, we became the sole managing member of SSE Holdings and, although we had a minority economic interest in SSE Holdings, we had the sole voting power in, and control the management of, SSE Holdings. Accordingly, we consolidated the financial results of SSE Holdings and reported a non-controlling interest in our consolidated financial statements. As the Organizational Transactions are considered transactions between entities under common control, the financial statements for periods prior to the IPO and Organizational Transactions have been adjusted to combine the previously separate entities for presentation purposes. Secondary Offering In August 2015, we completed a secondary offering of 4,000,000 shares of our Class A common stock at a price of $60.00 per share. All of the shares sold in the offering were offered by certain non-controlling interest holders. We did not receive any proceeds from the sale of shares of Class A common stock offered by the aforementioned non-controlling interest holders. The shares sold in the offering consisted of (i) 844,727 existing shares of Class A common stock held and (ii) 3,155,273 newly-issued shares of Class A common stock issued in connection with the redemption of 3,155,273 LLC Interests by the non-controlling interest holders that participated in the offering. Simultaneously, and in connection with the redemption, 3,155,273 shares of Class B common stock were surrendered by non-controlling interest holders and canceled. Additionally, in connection with the redemption, we received 3,155,273 LLC Interests, increasing our total ownership interest in SSE Holdings. USC Merger Pursuant to a Stockholders Agreement, dated as of February 4, 2015, as amended, by and among Daniel H. Meyer and his affiliates (the "Meyer Group") and other parties thereto, the Meyer Group has the right to cause all of the stock of Union Square Cafe Corp. ("USC") and Gramercy Tavern Corp. ("GT") to be converted into and exchanged for shares of our Class A common stock pursuant to a tax-free reorganization (each, a "Reorganization"). In December 2015, the Meyer Group exercised their right with respect to USC. The Reorganization was structured as a two-step merger, whereby (i) a newly-formed wholly-owned subsidiary of the Company merged with and into USC, then (ii) USC merged with and into the Company (the foregoing transactions are collectively referred to as the "USC Merger"). Prior to the USC Merger, USC owned 1,727,804 LLC Interests and an equivalent number of shares of our Class B common stock. In the USC Merger, (i) 1,727,804 shares of Class A common stock were issued to the stockholders of USC, with each stockholder receiving newly-issued shares of Class A common stock in an amount equivalent to the number of shares of USC held by such stockholders; (ii) 1,727,804 shares of Class B common stock held by USC were cancelled; and (iii) 1,727,804 LLC Interests held by USC were transferred to us. As of December 27, 2017 , we owned 72.1% of SSE Holdings and the non-controlling interest holders own the remaining 27.9% of SSE Holdings.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 27, 2017
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and include our accounts and the accounts of our subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior period amounts to conform to the current year presentation. SSE Holdings is considered a variable interest entity. Shake Shack Inc. is the primary beneficiary as we have the majority economic interest in SSE Holdings and, as the sole managing member, have decision making authority that significantly affects the economic performance of the entity, while the limited partners have no substantive kick-out or participating rights. As a result, we will continue to consolidate SSE Holdings. The assets and liabilities of SSE Holdings represent substantially all of our consolidated assets and liabilities with the exception of certain deferred taxes and liabilities under the Tax Receivable Agreement. As of December 27, 2017 and December 28, 2016 , the net assets of SSE Holdings were $197,301 and $158,845 , respectively. The assets of SSE Holdings are subject to certain restrictions in SSE Holdings' revolving credit agreements. See Note 8 for more information. Fiscal Year We operate on a 52/53 week fiscal year ending on the last Wednesday in December. Fiscal year 2017 contained 52 weeks and ended on December 27, 2017 . Fiscal year 2016 contained 52 weeks and ended on December 28, 2016 . Fiscal year 2015 contained 52 weeks and ended on December 30, 2015 . Unless otherwise stated, references to years in this report relate to fiscal years. Use of Estimates The preparation of these consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of sales and expenses during the reporting period. Actual results could differ from those estimates. Segment Reporting We own and operate Shacks in the United States. We also have domestic and international licensed operations. Our chief operating decision maker (the "CODM") is our Chief Executive Officer. As the CODM reviews financial performance and allocates resources at a consolidated level on a recurring basis, we have one operating segment and one reportable segment. Fair Value Measurements We apply fair value accounting for all financial assets and liabilities and non-financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis. Fair value is defined as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities that are required to be recorded at fair value, we assume the highest and best use of the asset by market participants in which we would transact and the market-based risk measurements or assumptions that market participants would use in pricing the asset or liability, such as inherent risk, transfer restrictions, and credit risk. Assets and liabilities are classified using a fair value hierarchy, which prioritizes the inputs used to measure fair value into three levels, and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: ▪ Level 1 - Quoted prices in active markets for identical assets or liabilities ▪ Level 2 - Observable inputs other than quoted prices in active markets for identical assets or liabilities, quoted prices for identical assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities ▪ Level 3 - Inputs that are both unobservable and significant to the overall fair value measurements reflecting an entity's estimates of assumptions that market participants would use in pricing the asset or liability Cash and Cash Equivalents Cash and cash equivalents consist primarily of cash on hand, deposits with banks, and short-term, highly liquid investments that have original maturities of three months or less. Cash equivalents are stated at cost, which approximates fair value. Cash equivalents consist primarily of money market funds. Accounts Receivable Accounts receivable consist primarily of receivables from landlords for tenant improvement allowances, receivables from our licensees for licensing revenue and related reimbursements, credit card receivables and vendor rebates. We evaluate the collectibility of our accounts receivable based on a variety of factors, including historical experience, current economic conditions and other factors. Inventories Inventories, which consist of food, beer, wine, other beverages and retail merchandise, are stated at the lower of cost or net realizable value with cost determined on a first-in, first-out basis. No adjustment is deemed necessary to reduce inventory to net realizable value due to the rapid turnover and high utilization of inventory. Property and Equipment Property and equipment is stated at historical cost less accumulated depreciation. Property and equipment is depreciated based on the straight-line method over the estimated useful lives of the assets, generally ranging from three to seven years for equipment, furniture and fixtures, and computer equipment and software. Leasehold improvements are depreciated over the shorter of their estimated useful life or the related lease life, generally ranging from 10 to 15 years. Landlord funded assets are depreciated over the shorter of their estimated useful life or the related lease life, generally ranging from 10 to 15 years. For leases with renewal periods at our option, we use the original lease term, excluding renewal option periods, to determine estimated useful lives. Costs incurred when constructing Shacks are capitalized. The cost of repairs and maintenance are expensed when incurred. Costs for refurbishments and improvements that significantly increase the productive capacity or extend the useful life of the asset are capitalized. When assets are disposed of, the resulting gain or loss is recognized on the Consolidated Statements of Income (Loss). We assess potential impairments to our long-lived assets, which includes property and equipment, whenever events or circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of an asset is measured by a comparison of the carrying amount of an asset group to its estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of the asset group exceeds its estimated undiscounted future cash flows, an impairment charge is recognized as the amount by which the carrying amount of the asset exceeds the fair value of the asset. There were no impairment charges recorded in fiscal 2017 , 2016 and 2015 . Deferred Financing Costs Deferred financing costs incurred in connection with the issuance of long-term debt and establishing credit facilities are capitalized and amortized to interest expense based on the related debt agreements. Deferred financing costs are included in other assets on the Consolidated Balance Sheets. Other Assets Other assets consist primarily of long-term marketable securities, security deposits, transferable liquor licenses and certain custom furniture pre-ordered for future Shacks and yet to be placed in service. The costs of obtaining non-transferable liquor licenses that are directly issued by local government agencies for nominal fees are expensed as incurred. The costs of purchasing transferable liquor licenses through open markets in jurisdictions with a limited number of authorized liquor licenses are capitalized as indefinite-lived intangible assets. Annual liquor license renewal fees are expensed over the renewal term. As of December 27, 2017 and December 28, 2016 , indefinite-lived intangible assets relating to transferable liquor licenses totaled $894 and $701 , respectively. We evaluate our indefinite-lived intangible assets for impairment annually during our fiscal fourth quarter, and whenever events or changes in circumstances indicate that an impairment may exist. When evaluating other intangible assets for impairment, we may first perform a qualitative assessment to determine whether it is more likely than not that an intangible asset group is impaired. If we do not perform the qualitative assessment, or if we determine that it is not more likely than not that the fair value of the intangible asset group exceeds its carrying amount, we calculate the estimated fair value of the intangible asset group. If the carrying amount of the intangible asset group exceeds the estimated fair value, an impairment charge is recorded to reduce the carrying value to the estimated fair value. In addition, we continuously monitor and may revise our intangible asset useful lives if and when facts and circumstances change. Equity-based Compensation Equity-based compensation expense is measured based on fair value. For awards with graded-vesting features and service conditions only, compensation expense is recognized on a straight-line basis over the total requisite service period for the entire award. For awards with graded-vesting features and a combination of service and performance conditions, compensation expense is recognized using a graded-vesting attribution method over the vesting period based on the most probable outcome of the performance conditions. Forfeitures are recognized as they occur for all equity awards. Equity-based compensation expense is included within general and administrative expenses and labor and related expenses on the Consolidated Statements of Income (Loss) . Leases We lease all of our domestic company-operated Shacks, our home office and certain equipment under various non-cancelable lease agreements that expire on various dates through 2035. Generally, our real estate leases have initial terms ranging from 10 to 15 years and typically include two five -year renewal options. At the inception of each lease, we determine its classification as an operating or capital lease. Most of our leases are classified as operating leases and typically provide for fixed minimum rent payments and/or contingent rent payments based upon sales in excess of specified thresholds. When the achievement of such sales thresholds are deemed to be probable, contingent rent is accrued in proportion to the sales recognized during the period. For operating leases that include rent holidays and rent escalation clauses, we recognize rent expense on a straight-line basis over the lease term from the date we take possession of the leased property. The difference between the straight-line rent amounts and amounts payable under the lease agreements is recorded as deferred rent and is included as rent expense in occupancy and related expenses on the Consolidated Statements of Income (Loss) . Rent expense incurred before a Shack opens is recorded in pre-opening costs. Once a domestic company-operated Shack opens, we record the straight-line rent expense and any contingent rent, if applicable, in occupancy and related expenses on the Consolidated Statements of Income (Loss) . Many of our leases also require us to pay real estate taxes, common area maintenance costs and other occupancy costs which are included in occupancy and related expenses on the Consolidated Statements of Income (Loss) . We expend cash for leasehold improvements to build out and equip our leased premises. Generally, a portion of the leasehold improvements and building costs are reimbursed by our landlords as landlord incentives pursuant to agreed-upon terms in our lease agreements. If obtained, landlord incentives usually take the form of up-front cash, full or partial credits against our future minimum or contingent rents otherwise payable by us, or a combination thereof. When contractually due, we classify landlord incentives as deferred rent on the Consolidated Balance Sheets and amortize the landlord incentives on a straight-line basis over the lease term as a reduction of occupancy costs and related expenses or pre-opening costs on the Consolidated Statements of Income (Loss) . Lease Financing Arrangements In certain leasing arrangements, due to our involvement in the construction of the leased assets, we are considered the owner of the leased assets for accounting purposes. In such cases, in addition to capitalizing our own construction costs, we capitalize the construction costs funded by the landlord related to our leased premises, and also recognize a corresponding liability for those costs as deemed landlord financing. If, upon completion of construction, the arrangement does not meet the sales recognition criteria under the sale-leaseback accounting guidance, we are precluded from de-recognizing the landlord-funded asset and related financing obligation and continue to account for the landlord-funded asset as if we were the legal owner. If de-recognition is permitted we are required to account for the lease as either an operating or capital lease. As of December 27, 2017 , we were deemed to be the accounting owner of 23 leased Shacks, 11 of which were under construction as of the end of the period. As of December 28, 2016 , we were deemed to be the accounting owner of eight leased Shacks, all of which were under construction as of the end of the period. Revenue Recognition Revenue consists of Shack sales and licensing revenue. Revenue from Shack sales are presented net of discounts and recognized when food and beverage products are sold. Sales tax collected from customers is excluded from Shack sales and the obligation is included in sales tax payable until the taxes are remitted to the appropriate taxing authorities. Revenue from our gift cards are deferred and recognized upon redemption. Licensing revenues include initial territory fees, restaurant opening fees, and ongoing licensing fees from licensed Shacks. Initial territory fees are recorded as deferred revenue when received and recognized as revenue on a straight-line basis over the term of the licensing agreement. Restaurant opening fees are recorded as deferred revenue when received, and recognized as revenue when a licensed Shack is opened and all material services and conditions related to the fee have been substantially performed. Ongoing licensing fees from these Shacks are based on a percentage of sales and are recognized as revenue as the fees are earned and become receivable from the licensee. Income Taxes We account for income taxes pursuant to the asset and liability method which requires the recognition of deferred income tax assets and liabilities related to the expected future tax consequences arising from temporary differences between the carrying amounts and tax bases of assets and liabilities based on enacted statutory tax rates applicable to the periods in which the temporary differences are expected to reverse. Any effects of changes in income tax rates or laws are included in income tax expense in the period of enactment. A valuation allowance is recognized if we determine it is more likely than not that all or a portion of a deferred tax asset will not be recognized. Pre-Opening Costs Pre-opening costs are expensed as incurred and consist primarily of legal fees, marketing expenses, occupancy, manager and employee wages, travel and related training costs incurred prior to the opening of a Shack. Advertising The cost of advertising is expensed as incurred. Advertising costs amounted to $357 , $147 and $149 in fiscal 2017 , 2016 and 2015 , respectively, and are included in general and administrative expense and other operating expenses on the Consolidated Statements of Income (Loss) . Recently Adopted Accounting Pronouncements We adopted the Accounting Standards Updates (“ASUs”) summarized below in fiscal 2017. The effects of adoption did not have a material impact on our consolidated financial statements. Accounting Standards Update (“ASU”) Description Date Adopted Improvements to Employee Share-Based Payment Accounting (ASU 2016-09) This standard simplifies certain aspects of accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, certain classifications on the statement of cash flows, and an option to recognize gross stock compensation expense with actual forfeitures recognized as they occur. Upon adoption, we made such policy election. The adoption methodology applied varied based on each applicable provision of the standard, and none of the provisions had a material impact on our consolidated financial statements. December 29, 2016 Simplifying the Measurement of Inventory (ASU 2015-11) This standard applies to inventory measured using methods other than last-in, first-out (LIFO) or the retail method, and requires entities to measure such inventory at the lower of cost or net realizable value. It was applied prospectively. December 29, 2016 Recently Issued Accounting Pronouncements Accounting Standards Update (“ASU”) Description Expected Impact Effective Date Statement of Cash Flows: Classification of Certain Cash Receipts and Payments (ASU 2016-15) This standard provides guidance on eight specific cash flow issues with the objective of reducing diversity in practice. It should be applied retrospectively to each period presented, subject to certain conditions. We do not expect this standard to have a material impact on our consolidated financial statements. December 28, 2017 Recognition and Measurement of Financial Assets and Financial Liabilities (ASU 2016-01) For public business entities, this standard requires: (i) certain equity investments to be measured at fair value with changes in fair value recognized in net income; (ii) a qualitative assessment to identify impairment of equity investments without readily determinable fair values; (iii) elimination of the requirement to disclose the method(s) and significant assumptions used to estimate the fair value for financial instruments measured at amortized cost on the balance sheet; (iv) use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (v) separate presentation in other comprehensive income of the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value in accordance with the fair value option for financial instruments; (vi) separate presentation of financial assets and liabilities by measurement category and form of financial asset in the financial statements; and (vii) an entity to evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the entity’s other deferred tax assets. The standard should be applied by means of a cumulative-effect adjustment to the balance sheet at the beginning of the fiscal year of adoption. Early adoption is permitted, subject to certain conditions resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value. We do not expect this standard to have a material impact on our consolidated financial statements. December 28, 2017 Leases (ASU 2016-02, 2018-01) This standard establishes a new lease accounting model, which introduces the recognition of lease assets and liabilities for those leases classified as operating leases under previous GAAP. It should be applied using a modified retrospective approach, with the option to elect various practical expedients. Early adoption is permitted. We are currently evaluating the impact this standard will have on our consolidated financial statements. We have developed an implementation project plan, and are in process of identifying the complete population of leases to be analyzed under the new standard. We plan to adopt the standard on December 27, 2018. December 27, 2018 Accounting Standards Update (“ASU”) Description Expected Impact Effective Date Revenue from Contracts with Customers and related standards (ASU’s 2014-09, 2015-14, 2016-08, 2016-10, 2016-12, 2016-20) This standard supersedes the existing revenue recognition guidance and provides a new framework for recognizing revenue. The core principle of the standard is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. The new standard also requires significantly more comprehensive disclosures than the existing standard. Guidance subsequent to ASU 2014-09 has been issued to clarify various provisions in the standard, including principal versus agent considerations, identifying performance obligations, licensing transactions, as well as various technical corrections and improvements. This standard may be adopted using either a retrospective or modified retrospective method. Early adoption is permitted. We are substantially complete with our evaluation of the impact this standard is expected to have on our consolidated financial statements. Licensing revenue Revenue recognition related to sales-based royalties, which represents a significant portion of the licensing revenue balance, will not change from current policy. However, the pattern and timing of revenue recognition related to the fixed fees associated with our licensing agreements (such as restaurant opening and initial territory fees) will differ from current policy. Currently, restaurant opening fees are recorded as deferred revenue when received and proportionate amounts are recognized as revenue when a licensed Shack is opened and all material services and conditions related to the fee have been substantially performed. Territory fees are recorded as deferred revenue when received and recognized as revenue on a straight-line basis over the term of the license agreement, which generally begins upon execution of the contract. Under the new standard, the license granted to each restaurant under each existing contract is considered a performance obligation. All other promises (such as providing assistance during the opening of a restaurant) will be combined with the license as one performance obligation. Accordingly, we will allocate the total transaction price (comprised of the restaurant opening and territory fees) to each restaurant expected to be opened by the licensee under the contract. We will recognize the fee allocated to each restaurant as revenue on a straight-line basis over the restaurant’s license term, which generally begins when the restaurant opens. Shack sales We do not currently expect a significant impact to Shack sales as a result of the new revenue standard. Adoption and transition adjustment We plan to adopt the standard on December 28, 2017, utilizing a modified retrospective transition approach. The adoption will result in a decrease to retained earnings of approximately $1,574 on the transition date, with a corresponding increase of $1,769 in other long-term liabilities, a decrease of $68 in other current liabilities, an increase of $100 to accounts receivable, with the remaining impact representing the tax impact of the transition adjustment, as an increase to deferred tax assets. December 28, 2017

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 27, 2017
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Assets and Liabilities Measured at Fair Value on a Recurring Basis The following tables present information about our financial assets and liabilities measured at fair value on a recurring basis as of December 27, 2017 and December 28, 2016 , and indicate the classification within the fair value hierarchy. Refer to Note 2 for further information. Cash, Cash Equivalents and Marketable Securities The following tables summarize our cash, cash equivalents and marketable securities by significant investment categories as of December 27, 2017 and December 28, 2016 : December 27, 2017 Cost Basis Gross Unrealized Gains Gross Unrealized Losses Fair Value Cash and Cash Equivalents Marketable Securities Cash $ 16,138 $ — $ — $ 16,138 $ 16,138 $ — Level 1: Money market funds 5,369 — — 5,369 5,369 — Mutual funds 60,985 61 (122 ) 60,924 — 60,924 Level 2: Corporate debt securities (1) 2,125 2 (15 ) 2,112 — 2,112 Total $ 84,617 $ 63 $ (137 ) $ 84,543 $ 21,507 $ 63,036 December 28, 2016 Cost Basis Gross Unrealized Gains Gross Unrealized Losses Fair Value Cash and Cash Equivalents Marketable Securities Cash $ 6,322 $ — $ — $ 6,322 $ 6,322 $ — Level 1: Money market funds 5,285 — — 5,285 5,285 — Mutual funds 60,232 — — 60,232 — 60,232 Level 2: Corporate debt securities (1) 2,473 3 (30 ) 2,446 — 2,446 Total $ 74,312 $ 3 $ (30 ) $ 74,285 $ 11,607 $ 62,678 (1) Corporate debt securities were measured at fair value using a market approach utilizing observable prices for identical securities or securities with similar characteristics and inputs that are observable or can be corroborated by observable market data. Net unrealized losses on available-for-sale securities totaling $74 and $27 were included in accumulated other comprehensive loss on the Consolidated Balance Sheet as of December 27, 2017 and December 28, 2016 , respectively. The following tables summarize the gross unrealized losses and fair values for those investments that were in an unrealized loss position as of December 27, 2017 and December 28, 2016 , aggregated by investment category and the length of time that individual securities have been in a continuous loss position: December 27, 2017 Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Money market funds $ — $ — $ — $ — $ — $ — Mutual funds — — — — — — Corporate debt securities 1,675 (12 ) 162 (3 ) 1,837 (15 ) Total $ 1,675 $ (12 ) $ 162 $ (3 ) $ 1,837 $ (15 ) December 28, 2016 Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Money market funds $ — $ — $ — $ — $ — $ — Mutual funds — — — — — — Corporate debt securities 1,244 (10 ) 540 (20 ) 1,784 (30 ) Total $ 1,244 $ (10 ) $ 540 $ (20 ) $ 1,784 $ (30 ) A summary of other income from available-for-sale securities recognized during fiscal 2017 , 2016 and 2015 is as follows: 2017 2016 2015 Available-for-sale securities: Dividend income $ 830 $ 296 $ — Interest income 77 88 7 Loss on investments (5 ) (7 ) — Total other income, net $ 902 $ 377 $ 7 A summary of available-for-sale securities sold and gross realized gains and losses recognized during fiscal 2017 and 2016 is as follows: 2017 2016 Available-for-sale securities: Gross proceeds from sales and redemptions $ 2,223 $ 938 Cost basis of sales and redemptions 2,271 956 Gross realized gains included in net income 1 2 Gross realized losses included in net income (49 ) (20 ) Amounts reclassified out of accumulated other comprehensive loss 47 19 No available-for-sale securities were sold or redeemed during fiscal 2015 . Realized gains and losses are determined on a specific identification method and are included in other income, net on the Consolidated Statements of Income (Loss) . The following table summarizes the estimated fair value of our investments in marketable debt securities, accounted for as available-for-sale securities and classified by the contractual maturity date of the securities: December 27 Due within one year $ 2,112 Due after one year through 5 years — Due after 5 years through 10 years — Due after 10 years — Total $ 2,112 We periodically review our marketable securities for other-than-temporary impairment. We consider factors such as the duration, severity and the reason for the decline in value, the potential recovery period and our intent to sell. For our debt securities, we also consider whether (i) it is more likely than not that we will be required to sell the debt securities before recovery of their amortized cost basis, and (ii) the amortized cost basis cannot be recovered as a result of credit losses. As of December 27, 2017 and December 28, 2016 , the declines in the market value of our marketable securities investment portfolio are considered to be temporary in nature. Other Financial Instruments The carrying value of our financial instruments, including accounts receivable, accounts payable, and accrued expenses as of December 27, 2017 and December 28, 2016 approximated their fair value due to the short-term nature of these financial instruments. Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis Assets and liabilities that are measured at fair value on a non-recurring basis include our long-lived assets and indefinite-lived intangible assets. There were no impairments recognized during fiscal 2017 , 2016 and 2015 .

ACCOUNTS RECEIVABLE

ACCOUNTS RECEIVABLE	12 Months Ended
	Dec. 27, 2017
Receivables [Abstract]
ACCOUNTS RECEIVABLE	ACCOUNTS RECEIVABLE The components of accounts receivable as of December 27, 2017 and December 28, 2016 are as follows: December 27 December 28 Landlord receivables $ 1,660 $ 2,606 Licensing receivables 1,422 1,278 Credit card receivables 2,018 1,589 Other receivables 541 533 Accounts receivable $ 5,641 $ 6,006 As of December 27, 2017 and December 28, 2016 , no allowance for doubtful accounts was recorded based on our evaluation of collectibility.

INVENTORIES

INVENTORIES	12 Months Ended
	Dec. 27, 2017
Inventory Disclosure [Abstract]
INVENTORIES	INVENTORIES Inventories consisted of the following: December 27 December 28 Food $ 874 $ 543 Wine 69 47 Beer 85 58 Beverages 111 79 Retail merchandise 119 79 Inventories $ 1,258 $ 806

PROPERTY AND EQUIPMENT

PROPERTY AND EQUIPMENT	12 Months Ended
	Dec. 27, 2017
Property, Plant and Equipment [Abstract]
PROPERTY AND EQUIPMENT	PROPERTY AND EQUIPMENT Property and equipment consisted of the following: December 27 December 28 Leasehold improvements $ 166,963 $ 120,629 Landlord funded assets 7,472 — Equipment 31,608 23,194 Furniture and fixtures 10,128 7,342 Computer equipment and software 12,721 8,710 Construction in progress (includes assets under construction from deemed landlord financing) 16,458 13,510 Property and equipment, gross 245,350 173,385 Less: accumulated depreciation (58,255 ) (37,121 ) Property and equipment, net $ 187,095 $ 136,264 Depreciation expense was $21,704 , $14,502 and $10,222 for fiscal 2017 , 2016 and 2015 , respectively.

SUPPLEMENTAL BALANCE SHEET INFO

SUPPLEMENTAL BALANCE SHEET INFORMATION	12 Months Ended
	Dec. 27, 2017
Supplemental Balance Sheet Disclosures [Abstract]
SUPPLEMENTAL BALANCE SHEET INFORMATION	SUPPLEMENTAL BALANCE SHEET INFORMATION The components of other current liabilities as of December 27, 2017 and December 28, 2016 are as follows: December 27 December 28 Sales tax payable $ 1,813 $ 1,324 Current portion of liabilities under tax receivable agreement 937 4,580 Gift card liability 1,472 1,153 Other 3,715 3,116 Other current liabilities $ 7,937 $ 10,173

DEBT

DEBT	12 Months Ended
	Dec. 27, 2017
Debt Disclosure [Abstract]
DEBT	DEBT In January 2015, we executed a Third Amended and Restated Credit Agreement, which became effective on February 4, 2015 (together with the prior agreements and amendments, and as further amended, the "Revolving Credit Facility"), which provides for a total revolving commitment amount of $50,000 , of which $20,000 is available immediately. The Revolving Credit Facility will mature and all amounts outstanding will be due and payable five years from the effective date. The Revolving Credit Facility permits the issuance of letters of credit upon our request of up to $10,000 . In May 2016, the Revolving Credit Facility was amended to, among other things, lower the borrowing rates. Borrowings under the Revolving Credit Facility bear interest at either: (i) LIBOR plus a percentage ranging from 2.3% to 3.3% or (ii) the prime rate plus a percentage ranging from 0.0% to 0.8% , depending on the type of borrowing made under the Revolving Credit Facility. As of December 27, 2017 and December 28, 2016 , there were no amounts outstanding under the Revolving Credit Facility. As of December 27, 2017 , we had $19,317 of availability under the Revolving Credit Facility, after giving effect to $683 in outstanding letters of credit. The Revolving Credit Facility is secured by a first-priority security interest in substantially all of the assets of SSE Holdings and the guarantors. The obligations under the Revolving Credit Facility are guaranteed by each of SSE Holdings' wholly-owned domestic subsidiaries (with certain exceptions). The Revolving Credit Facility contains a number of covenants that, among other things, limit our ability to, subject to specified exceptions, incur additional debt; incur additional liens and contingent liabilities; sell or dispose of assets; merge with or acquire other companies; liquidate or dissolve ourselves; pay dividends or make distributions; engage in businesses that are not in a related line of business; make loans, advances or guarantees; engage in transactions with affiliates; and make investments. In addition, the Revolving Credit Facility contains certain cross-default provisions. We are required to maintain a specified consolidated fixed-charge coverage ratio and a specified funded net debt to adjusted EBITDA ratio, both as defined under the Revolving Credit Facility. As of December 27, 2017 , we were in compliance with all covenants. In March 2013, we entered into a promissory note in the amount of $313 in connection with the purchase of a liquor license. Interest on the outstanding principal balance of this note is due and payable on a monthly basis from the effective date at a rate of 5.0% per year. During the fiscal year ended December 28, 2016 , we repaid the entire outstanding balance of the promissory note. No amounts were outstanding as of December 27, 2017 and December 28, 2016 . As of December 27, 2017 and December 28, 2016 we had deemed landlord financing liabilities of $14,518 and $2,007 , respectively, for certain leases where we are involved in the construction of leased assets and are considered the accounting owner of the construction project. Refer to Note 9 for further details regarding these leases. Total interest costs incurred were $1,806 , $374 and $440 in fiscal 2017 , 2016 and 2015 , respectively. Amounts capitalized into property and equipment were $164 and $108 during fiscal 2017 and 2015 , respectively. No amounts were capitalized into property and equipment during fiscal 2016 .

LEASES

LEASES	12 Months Ended
	Dec. 27, 2017
Leases [Abstract]
LEASES	LEASES A summary of rent expense under operating lease agreements is as follows: 2017 2016 2015 Minimum rent $ 20,421 $ 15,408 $ 10,796 Deferred rent 838 2,122 1,482 Contingent rent 4,902 4,294 2,959 Total rent expense $ 26,161 $ 21,824 $ 15,237 The rent expense above does not include common area maintenance costs, real estate taxes and other occupancy costs, which were $4,570 , $3,229 and $2,119 in fiscal 2017 , 2016 and 2015 , respectively. As of December 27, 2017 , future minimum lease payments under non-cancelable operating leases and lease financing arrangements consisted of the following: Operating Leases Deemed Landlord Financing (1) 2018 $ 24,123 $ 3,679 2019 26,045 4,614 2020 25,817 4,695 2021 26,076 4,747 2022 26,506 4,816 Thereafter 143,244 27,438 Total minimum lease payments $ 271,811 $ 49,989 (1) Amounts include minimum lease payments for 11 leases under construction as of December 27, 2017 where we are deemed the accounting owner. Final classification of lease payments under deemed landlord financing is subject to change pending sale lease-back analysis performed at the store opening date. As of December 27, 2017 , we had 23 leases where we are involved in the construction of the leased assets and have been deemed the accounting owner of the construction project. The deemed landlord financing liability related to these leases was $14,518 as of December 27, 2017 . As of December 28, 2016 , we had eight leases where we are involved in the construction of the leased assets and have been deemed the accounting owner of the construction project. The deemed landlord financing liability related to those leases was $2,007 as of December 28, 2016 .

EMPLOYEE BENEFIT PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Dec. 27, 2017
Compensation Related Costs [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS Deferred Compensation During fiscal 2013, we entered into an incentive bonus agreement with one of our executives, whereby the executive is entitled to receive a deferred compensation award in the amount of $2,450 , payable by us in March 2018, and is included in other current liabilities on the Consolidated Balance Sheet. In fiscal 2013, we recorded $2,054 of deferred compensation expense to recognize the present value of the incentive bonus liability, which is included in other long-term liabilities on the Consolidated Balance Sheet. The deferred compensation expense is included within general and administrative expense on the Consolidated Statement of Income (Loss) . There was no such expense in fiscal 2017, 2016 or 2015. The difference between the present value of the bonus liability and the amount payable is accreted to interest expense over the remaining term until the incentive bonus becomes payable. In September 2015, we established a grantor trust, commonly referred to as a "rabbi trust," for the purpose of funding our deferred compensation obligation. We contributed $2,450 to the trust in October 2015. Assets held by the trust are subject to creditor claims in the event of insolvency, but are not available for general corporate purposes. As of December 27, 2017 , amounts held by the trust were invested in various marketable securities classified as available-for-sale and recognized at fair value on the Consolidated Balance Sheet. See Note 3 . Defined Contribution Plan Our employees are eligible to participate in a defined contribution savings plan maintained by Union Square Hospitality Group, LLC, a related party. The plan is funded by employee and employer contributions. We pay our share of the employer contributions directly to the third party trustee. Employer contributions to the plan are at our discretion. Effective January 2014, we began making contributions matching a portion of participants' contributions. We match 100% of participants' contributions for the first 3% of eligible compensation contributed and 50% of contributions made in excess of 3% of eligible compensation up to 5% of eligible compensation. Employer contributions totaled $389 , $257 and $238 for fiscal 2017 , 2016 and 2015 , respectively.

STOCKHOLDER'S EQUITY

STOCKHOLDER'S EQUITY	12 Months Ended
	Dec. 27, 2017
Equity [Abstract]
STOCKHOLDER'S EQUITY	STOCKHOLDERS' EQUITY Amendment and Restatement of Certificate of Incorporation On February 4, 2015, we amended and restated our certificate of incorporation to, among other things, provide for the (i) authorization of 200,000,000 shares of Class A common stock with a par value of $0.001 per share; (ii) authorization of 35,000,000 shares of Class B common stock with a par value of $0.001 per share; (iii) authorization of 10,000,000 shares of undesignated preferred stock that may be issued from time to time by our Board of Directors in one or more series; and (iv) establishment of a classified board of directors, divided into three classes, each of whose members will serve for staggered three -year terms. Holders of our Class A and Class B common stock are entitled to one vote per share and, except as otherwise required, will vote together as a single class on all matters on which stockholders generally are entitled to vote. Holders of our Class B common stock are not entitled to receive dividends and will not be entitled to receive any distributions upon the liquidation, dissolution or winding up of the Company. Shares of Class B common stock may only be issued to the extent necessary to maintain the one -to-one ratio between the number of LLC Interests held by the non-controlling interest holders and the number of shares of Class B common stock held by the non-controlling interest holders. Shares of Class B common stock are transferable only together with an equal number of LLC Interests. Shares of Class B common stock will be canceled on a one -for-one basis upon the redemption or exchange of any of the outstanding LLC Interests. We must, at all times, maintain a one -to-one ratio between the number of outstanding shares of Class A common stock and the number of LLC Interests owned by us (subject to certain exceptions for treasury shares and shares underlying certain convertible or exchangeable securities). Initial Public Offering As described in Note 1 , on February 4, 2015, we completed an IPO of 5,750,000 shares of our Class A common stock at a public offering price of $21.00 per share, which includes 750,000 shares issued pursuant to the underwriters' over-allotment option. We received $112,298 in proceeds, net of underwriting discounts and commissions, which we used to purchase newly-issued LLC Interests from SSE Holdings at a price per interest equal to the initial public offering price of our Class A common stock. In connection with our IPO, we issued 30,160,694 shares of Class B common stock to the non-controlling interest holders. SSE Holdings Recapitalization As described in Note 1 , on February 4, 2015, we amended the SSE Holdings LLC Agreement to, among other things, (i) provide for a new single class of common membership interests in SSE Holdings, the LLC Interests, and (ii) exchange all of the then-existing membership interests of the non-controlling interest holders for LLC Interests. The SSE Holdings LLC Agreement also provides that holders of LLC Interests may, from time to time, require SSE Holdings to redeem all or a portion of their LLC Interests for newly-issued shares of Class A common stock on a one -for-one basis. Upon receipt of a redemption request, we may, instead, elect to effect a direct exchange of LLC Interests directly with the holder. Additionally, we may elect to settle any such redemption or exchange in shares of Class A common stock or in cash. In the event of cash settlement, we would issue new shares of Class A common stock and use the proceeds from the sale of these newly-issued shares of Class A common stock to fund the cash settlement, which, in effect, limits the amount of the cash payment to the redeeming member. In connection with any redemption or exchange, we will receive a corresponding number of LLC Interests, increasing our total ownership interest in SSE Holdings. Additionally, an equivalent number of shares of Class B common stock will be surrendered and canceled. The amendment also requires that SSE Holdings, at all times, maintain (i) a one -to-one ratio between the number of outstanding shares of Class A common stock and the number of LLC Interests owned by us and (ii) a one -to-one ratio between the number of shares of Class B common stock owned by the non-controlling interest holders and the number of LLC Interests owned by the non-controlling interest holders. Secondary Offering As described in Note 1 , in August 2015, we completed a secondary offering of 4,000,000 shares of our Class A common stock at a price of $60.00 per share. All of the shares sold in the offering were offered by certain of the non-controlling interest holders. We did not receive any proceeds from the sale of shares of Class A common stock. The shares sold in the offering consisted of (i) 844,727 existing shares of Class A common stock and (ii) 3,155,273 newly-issued shares of Class A common stock issued in connection with the redemption of 3,155,273 LLC Interests. Simultaneously, and in connection with the secondary offering, 3,155,273 shares of Class B common stock were surrendered and cancelled. Mergers As described in Note 1 , we acquired, by merger, two entities that were owned by former indirect members of SSE Holdings, for which we issued 5,968,841 shares of Class A common stock as merger consideration. In connection with these mergers, 5,968,841 shares of Class B common stock were canceled and we received 5,968,841 of LLC Interests. Additionally, in December 2015, the Meyer Group exercised their right to effect of tax-free reorganization of USC pursuant to the Stockholders Agreement. Prior to the USC Merger, USC owned 1,727,804 LLC Interests and an equivalent number of shares of our Class B common stock. In connection with the USC Merger, (i) 1,727,804 shares of Class A common stock were issued to the stockholders of USC, with each stockholder receiving newly-issued shares of Class A common stock in an amount equivalent to the number of shares of USC held by such stockholders; (ii) 1,727,804 shares of Class B common stock held by USC were cancelled; and (iii) 1,727,804 LLC Interests held by USC were transferred to us. Member Distributions On December 15, 2014, the Board of Directors of SSE Holdings approved a special distribution to its members, to the extent the gross proceeds from the IPO exceeded the anticipated gross proceeds (including as a result of the exercise by the underwriters of their option to purchase additional shares of Class A common stock), in an amount equal to the product of (i) the increased gross proceeds and (ii) 0.273 , to be paid from the proceeds of the IPO (the "Special Distribution"). On February 4, 2015, SSE Holdings paid the Special Distribution to certain of the then-existing members in the amount of $11,125 . Redemptions of LLC Interests During fiscal 2017 , an aggregate of 1,003,585 LLC Interests were redeemed by the non-controlling interest holders. Pursuant to the SSE Holdings LLC Agreement, we issued 1,003,585 shares of Class A common stock in connection with these redemptions and received 1,003,585 LLC Interests, increasing our ownership interest in SSE Holdings. Simultaneously, and in connection with these redemptions, 1,003,585 shares of Class B common stock were surrendered and cancelled. During fiscal 2016 , an aggregate of 5,207,149 LLC Interests were redeemed by the non-controlling interest holders. Pursuant to the SSE Holdings LLC Agreement, we issued 5,207,149 shares of Class A common stock in connection with these redemptions and received 5,207,149 LLC Interests, increasing our ownership interest in SSE Holdings. Simultaneously, and in connection with these redemptions, 5,207,149 shares of Class B common stock were surrendered and cancelled. Stock Option Exercises We received an aggregate of 372,508 and 154,976 LLC Interests in connection with the exercise of employee stock options during fiscal 2017 and 2016 , respectively. Dividend Restrictions We are a holding company with no direct operations. As a result, our ability to pay cash dividends on our common stock, if any, is dependent upon cash dividends, distributions or other transfers from SSE Holdings. The amounts available to us to pay cash dividends are subject to certain covenants and restrictions set forth in the Revolving Credit Facility. As of December 27, 2017 , essentially all of the net assets of SSE Holdings were restricted. See Note 8 for more information regarding the covenants and restrictions set forth in the Revolving Credit Facility.

NON-CONTROLLING INTERESTS

NON-CONTROLLING INTERESTS	12 Months Ended
	Dec. 27, 2017
Noncontrolling Interest [Abstract]
NON-CONTROLLING INTERESTS	NON-CONTROLLING INTERESTS In connection with the Organizational Transactions described in Note 11, on February 4, 2015 we became the sole managing member of SSE Holdings and, as a result, consolidate the financial results of SSE Holdings. We report a non-controlling interest representing the economic interest in SSE Holdings held by the other members of SSE Holdings. The SSE Holdings LLC Agreement provides that holders of LLC Interests may, from time to time, require SSE Holdings to redeem all or a portion of their LLC Interests for newly-issued shares of Class A common stock on a one -for-one basis. In connection with any redemption or exchange, we will receive a corresponding number of LLC Interests, increasing our total ownership interest in SSE Holdings. Changes in our ownership interest in SSE Holdings while we retain our controlling interest in SSE Holdings will be accounted for as equity transactions. As such, future redemptions or direct exchanges of LLC Interests in SSE Holdings by the other members of SSE Holdings will result in a change in ownership and reduce the amount recorded as non-controlling interest and increase additional paid-in capital. The following table summarizes the ownership interest in SSE Holdings as of December 27, 2017 and December 28, 2016 : 2017 2016 LLC Interests Ownership % LLC Interests Ownership % Number of LLC Interests held by Shake Shack Inc. 26,527,477 72.1 % 25,151,384 69.1 % Number of LLC Interests held by non-controlling interest holders 10,250,007 27.9 % 11,253,592 30.9 % Total LLC Interests outstanding 36,777,484 100.0 % 36,404,976 100.0 % The weighted average ownership percentages for the applicable reporting periods are used to attribute net income and other comprehensive loss between Shake Shack Inc. and the non-controlling interest holders. The non-controlling interest holders' weighted average ownership percentage for fiscal 2017 and 2016 was 29.4% and 36.8% , respectively. The following table summarizes the effects of changes in ownership in SSE Holdings on our equity during fiscal 2017 , 2016 and 2015 . 2017 2016 2015 Net income (loss) attributable to Shake Shack Inc. $ (320 ) $ 12,446 $ (8,776 ) Other comprehensive loss: Unrealized holding losses on available-for-sale securities (34 ) (10 ) (5 ) Transfers (to) from non-controlling interests: Increase in additional paid-in capital as a result of settlement of unit appreciation rights — — 987 Decrease in additional paid-in capital as a result of the organizational transactions completed in connection with our IPO — — (75,182 ) Increase in additional paid-in capital as a result of the redemption of LLC Interests 4,415 16,986 19,934 Increase in additional paid-in capital as a result of the USC Merger — — 5,908 Increase in additional paid-in capital as a result of stock option exercises and the related income tax effect 4,451 825 — Total effect of changes in ownership interest on equity attributable to Shake Shack Inc. $ 8,512 $ 30,247 $ (57,134 ) In February 2015, we used the net proceeds from our IPO to purchase 5,750,000 newly-issued LLC Interests. Additionally, in connection with our IPO, we acquired 5,968,841 LLC Interests through the acquisition, by merger, of two entities that were owned by former indirect members of SSE Holdings. Pursuant to the SSE Holdings LLC Agreement, we received 339,306 LLC Interests as a result of the issuance of 339,306 shares of Class A common stock upon settlement of the outstanding UARs. In December 2015, we received 1,727,804 LLC Interests in connection with the USC Merger in exchange for an equivalent number of newly-issued shares of Class A common stock. During 2016 , an aggregate of 5,207,149 LLC Interests were redeemed by the non-controlling interest holders, and we received 5,207,149 LLC Interests, increasing our total ownership interest is SSE Holdings to 69.1% . During fiscal 2017 , an aggregate of 1,003,585 LLC Interests were redeemed by the non-controlling interest holders for newly-issued shares of Class A common stock, and we received 1,003,585 LLC Interests, increasing our total ownership interest in SSE Holdings to 72.1% . We received an aggregate of 372,508 and 154,976 LLC Interests in connection with the exercise of employee stock options during fiscal 2017 and 2016 , respectively.

EQUITY-BASED COMPENSATION

EQUITY-BASED COMPENSATION	12 Months Ended
	Dec. 27, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
EQUITY-BASED COMPENSATION	EQUITY-BASED COMPENSATION A summary of equity-based compensation expense recognized during fiscal 2017 , 2016 and 2015 is as follows: 2017 2016 2015 Unit appreciation rights $ — $ — $ 11,762 Restricted Class B units — — 605 Stock options 3,474 4,262 4,314 Performance stock units 1,869 1,092 — Restricted stock units 280 — — Equity-based compensation expense $ 5,623 $ 5,354 $ 16,681 Total income tax benefit recognized related to equity-based compensation $ 198 $ 168 $ 482 Amounts are included in general and administrative expense and labor and related expenses on the Consolidated Statements of Income (Loss) . We capitalized $109 and $139 of equity-based compensation in fiscal 2017 and 2016 , respectively. No amounts were capitalized in fiscal 2015 . Unit Appreciation Rights Prior to the IPO, we maintained a Unit Appreciation Rights Plan (the "UAR Plan"), effective in fiscal year 2012, and as amended, whereby we had the authority to grant up to 31,303 unit appreciation rights ("UARs") to employees. The UARs granted were subject to continued employment and were only exercisable upon a qualifying transaction. Our IPO constituted a qualifying transaction under the terms of the UAR Plan, and as a result 339,306 shares of Class A common stock were issued upon the settlement of the 22,554 outstanding UARs, net of employee withholding taxes. We recognized compensation expense of $11,762 during fiscal 2015 upon settlement of the outstanding UARs. There were no UARs outstanding as of December 27, 2017 or December 28, 2016 . No compensation expense was recognized during fiscal 2017 and 2016 . Restricted Class B Units Prior to the IPO, we granted restricted Class B units to certain of our executive officers. These awards were to vest in equal installments over periods ranging from three to five years. If not already fully vested, these units would fully vest (i) upon the occurrence of a change in control event or (ii) upon the occurrence of an initial public offering. The IPO constituted a transaction under the terms of the restricted Class B unit award agreements that resulted in the accelerated vesting of all then-outstanding awards, and we recognized $605 of equity-based compensation expense upon the vesting of these awards during fiscal 2015 . There were no restricted Class B units outstanding as of December 27, 2017 or December 28, 2016 . No compensation expense was recorded during fiscal 2017 and 2016 . Stock Options In January 2015, we adopted the 2015 Incentive Award Plan (the "2015 Plan") under which we may grant up to 5,865,522 stock options and other equity-based awards to employees, directors and officers. The stock options granted generally vest equally over periods ranging from one to five years. We do not use cash to settle any of our equity-based awards, and we issue new shares of Class A common stock upon the exercise of stock options. The fair value of stock option awards was determined on the grant date using the Black-Scholes valuation model based on the following weighted-average assumptions: 2017 2016 2015 Expected term (years) (1) 7.5 5.5 7.5 Expected volatility (2) 44.5 % 50.7 % 35.1 % Risk-free interest rate (3) 2.1 % 1.5 % 1.6 % Dividend yield (4) — % — % — % (1) Expected term represents the estimated period of time until an award is exercised and was determined using the simplified method. (2) Expected volatility is based on the historical volatility of a selected peer group over a period equivalent to the expected term. (3) The risk-free rate rate is an interpolation of yields on U.S. Treasury securities with maturities equivalent to the expected term. (4) We have assumed a dividend yield of zero as we have no plans to declare dividends in the foreseeable future. A summary of stock option activity for fiscal years 2017 , 2016 and 2015 is as follows: Stock Options Weighted Average Exercise Price Aggregate Intrinsic Value Weighted Average Remaining Contractual Life (Years) Outstanding as of December 31, 2014 — $ — Granted 2,622,281 21.00 Exercised — — Forfeited (47,300 ) (21.00 ) Expired — — Outstanding as of December 30, 2015 2,574,981 $ 21.00 Granted 16,931 34.74 Exercised (160,230 ) 21.00 Forfeited (66,960 ) (21.00 ) Expired — — Outstanding as of December 28, 2016 2,364,722 $ 21.10 Granted 5,150 38.91 Exercised (359,011 ) 21.13 Forfeited (291,520 ) (21.00 ) Expired — — Outstanding as of December 27, 2017 1,719,341 $ 21.16 $ 39,851 7.1 Options vested and exercisable as of December 27, 2017 543,246 $ 21.34 $ 12,493 7.1 Options expected to vest as of December 27, 2017 1,098,577 $ 21.08 $ 25,549 7.1 As of December 27, 2017 , total unrecognized compensation expense related to unvested stock options was $7,098 , which is expected to be recognized over a weighted-average period of 2.1 years. The total intrinsic value of stock options exercised during fiscal 2017 and 2016 was $8,333 and $2,536 , respectively. No stock options were exercised during fiscal 2015 . C ash received from stock option exercises was $7,585 for fiscal 2017 . A summary of unvested stock option activity for fiscal years 2017 , 2016 and 2015 is as follows: Stock Options Weighted Average Grant-Date Fair Value Unvested as of December 31, 2014 — $ — Vested — — Granted 2,622,281 8.53 Forfeited (47,300 ) 8.59 Unvested as of December 30, 2015 2,574,981 $ 8.53 Vested (562,296 ) 8.32 Granted 16,931 16.32 Forfeited (65,365 ) 8.59 Unvested as of December 28, 2016 1,964,251 $ 8.66 Vested (503,686 ) 8.85 Granted 5,150 19.42 Forfeited (289,620 ) 8.59 Unvested as of December 27, 2017 1,176,095 $ 8.64 The total fair value of stock options vested during fiscal 2017 and 2016 was $4,458 and $4,678 , respectively. No stock options vested during fiscal 2015 . The following table summarizes information about stock options outstanding and exercisable as December 27, 2017 : Options Outstanding Options Exercisable Number Outstanding at December 27, 2017 Weighted Average Remaining Contractual Life (Years) Weighted Average Exercise Price Number Exercisable at December 27, 2017 Weighted Average Remaining Contractual Life (Years) Weighted Average Exercise Price Exercise Price $21.00 1,700,665 7.1 $ 21.00 529,720 7.1 $ 21.00 $34.62 12,418 8.4 $ 34.62 12,418 8.4 $ 34.62 $36.41 1,108 8.9 $ 36.41 1,108 8.9 $ 36.41 $38.91 5,150 9.5 $ 38.91 — — $ — Performance Stock Units Under the 2015 Plan, we may grant performance stock units and other types of performance-based equity awards that vest based on the outcome of certain performance criteria that are established and approved by the Compensation Committee of the Board of Directors. The actual number of equity awards earned is based on the level of performance achieved over a predetermined performance period, relative to established financial goals, none of which are considered market conditions. For performance stock units granted during fiscal 2017 , the amount of awards that can be earned range from 0% to 125% of the number of performance stock units granted, based on the achievement of approved financial goals over a one -year performance period. In addition to the performance conditions, performance stock units are also subject to a requisite service period and the awards will vest ratably over three years. The fair value of performance stock units is determined based on the closing market price of our Class A common stock on the date of grant. Compensation expense related to the performance stock units is recognized using a graded-vesting attribution method over the vesting period based on the most probable outcome of the performance conditions. A summary of performance stock unit activity for fiscal years 2017 and 2016 is as follows: Performance Stock Units Weighted Average Grant Date Fair Value Outstanding as of December 30, 2015 — $ — Granted 63,600 38.41 Performance achievement (1) — — Vested — — Forfeited (2,000 ) 38.43 Expired — — Outstanding as of December 28, 2016 61,600 $ 38.41 Granted 87,596 37.90 Performance achievement (1) 9,545 38.40 Vested (22,703 ) 38.40 Forfeited (11,196 ) 38.28 Expired — — Outstanding as of December 27, 2017 124,842 $ 38.06 (1) Represents incremental awards earned based on the achievement of performance conditions. No performance stock units were granted in fiscal 2015 . As of December 27, 2017 , there were 124,842 performance stock units outstanding, of which none were vested. As of December 27, 2017 , total unrecognized compensation expense related to unvested performance stock units was $2,385 , which is expected to be recognized over a weighted-average period of 1.6 years. Restricted Stock Units Under the 2015 Plan, we may grant restricted stock units to employees, directors and officers. The restricted stock units granted generally vest equally over periods ranging from one to five years. T he fair value of restricted stock units is determined based on the closing market price of our Class A common stock on the date of grant. Compensation expense related to the restricted stock units is recognized using a straight-line attribution method over the vesting period. In fiscal 2017 , 44,476 restricted stock units were granted with a weighted average grant date fair value of $38.98 . As of December 27, 2017, there were 44,476 restricted stock units outstanding, of which none were vested. No restricted stock units were granted in fiscal 2016 and 2015 . As of December 27, 2017 , total unrecognized compensation expense related to unvested restricted stock units was $1,453 , which is expected to be recognized over a weighted-average period of 2.5 years.

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 27, 2017
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES We are the sole managing member of SSE Holdings, and as a result, consolidate the financial results of SSE Holdings. SSE Holdings is treated as a partnership for U.S. federal and most applicable state and local income tax purposes. As a partnership, SSE Holdings is not subject to U.S. federal and certain state and local income taxes. Any taxable income or loss generated by SSE Holdings is passed through to and included in the taxable income or loss of its members, including us, on a pro rata basis. We are subject to U.S. federal income taxes, in addition to state and local income taxes with respect to our allocable share of any taxable income or loss of SSE Holdings, as well as any stand-alone income or loss generated by Shake Shack Inc. We are also subject to withholding taxes in foreign jurisdictions. In December 2017, the Tax Cuts and Jobs Act of 2017 (the "TCJA") was enacted into law. The TCJA provides for significant changes to the U.S. Internal Revenue Code of 1986, as amended, including the reduction of the U.S. federal corporate income tax rate from 35% to 21%, among other provisions. We have calculated our best estimate of the impact of the TCJA based on current interpretations and understanding of the TCJA and recognized an additional $138,636 of income tax expense as a provisional amount, in accordance with Staff Accounting Bulletin No. 118 ("SAB 118"), relating to the remeasurement of our deferred tax assets. Any subsequent adjustment to these provisional amounts as a result of obtaining, preparing, or analyzing additional information about facts and circumstances that existed as of the enactment date will be recognized as income tax expense in fiscal 2018. Income Tax Expense The components of income before income taxes are follows: 2017 2016 2015 Domestic $ 152,204 $ 20,623 $ 244 Foreign 8,089 7,873 6,184 Income before income taxes $ 160,293 $ 28,496 $ 6,428 The components of income tax expense are as follows: 2017 2016 2015 Current income taxes: Federal $ 518 $ 3,767 $ 2,474 State and local 3,615 2,439 1,131 Foreign 942 667 433 Total current income taxes 5,075 6,873 4,038 Deferred income taxes: Federal 145,139 (48 ) (267 ) State and local 1,195 (475 ) (467 ) Total deferred income taxes 146,334 (523 ) (734 ) Income tax expense $ 151,409 $ 6,350 $ 3,304 Reconciliations of income tax expense computed at the U.S. federal statutory income tax rate to the recognized income tax expense and the U.S. statutory income tax rate to our effective tax rates are as follows: 2017 2016 2015 Expected U.S. federal income taxes at statutory rate $ 56,103 35.0 % $ 9,689 34.0 % $ 2,186 34.0 % State and local income taxes, net of federal benefit 2,590 1.6 % 1,461 5.1 % 663 10.3 % Foreign withholding taxes 942 0.6 % 667 2.3 % 433 6.7 % Non-deductible expenses 223 0.1 % 25 0.1 % 653 10.2 % Tax credits (1,230 ) (0.8 )% (779 ) (2.7 )% (141 ) (2.2 )% Non-controlling interest (3,273 ) (2.0 )% (3,765 ) (13.2 )% (490 ) (7.6 )% Remeasurement of deferred tax assets in connection with the enactment of the TCJA 138,636 86.5 % — — % — — % Remeasurement of deferred tax assets in connection with other tax rate changes 1,657 1.0 % (1,353 ) (4.7 )% — — % Remeasurement of liabilities under tax receivable agreement in connection with the enactment of the TCJA (44,051 ) (27.4 )% — — % — — % Other (188 ) (0.1 )% 405 1.4 % — — % Income tax expense $ 151,409 94.5 % $ 6,350 22.3 % $ 3,304 51.4 % Our effective income tax rates for fiscal 2017 , 2016 and 2015 were 94.5% , 22.3% and 51.4% , respectively. The increase in our effective income tax rate from fiscal 2016 to fiscal 2017 is primarily due to the remeasurement of deferred tax assets resulting from the enactment of the TCJA. The decrease in our effective income tax rate from fiscal 2015 to fiscal 2016 is due to the IPO and Organizational Transactions that occurred in fiscal 2015 . As the non-recurring compensation expenses and other IPO-related expenses recognized during fiscal 2015 were incurred in the period prior to the Organizational Transactions, and prior to our becoming a member of SSE Holdings, we were not entitled to any tax benefits related to those losses. We recognized tax expense in fiscal 2015 based on our allocable share of the taxable income generated in the period subsequent to our becoming a member of SSE Holdings, which resulted in a very high effective tax rate in fiscal 2015 when compared to our consolidated pre-tax income. Additionally, in fiscal 2016 , the effective tax rate was positively impacted by a tax benefit of $1,353 we recognized due to the impact from a tax rate change on our deferred tax assets, as well as other rate changes. Deferred Tax Assets and Liabilities The components of deferred tax assets and liabilities are as follows: December 27 December 28 Deferred tax assets: Investment in partnership $ 137,449 $ 209,648 Tax Receivable Agreement 43,464 110,022 Deferred rent 571 561 Deferred revenue 59 53 Stock-based compensation 322 331 Net operating loss carryforwards 12,332 7,338 Tax credits 2,328 1,084 Other assets 176 108 Total gross deferred tax assets 196,701 329,145 Valuation allowance (10,114 ) (15,568 ) Total deferred tax assets, net of valuation allowance 186,587 313,577 Deferred tax liabilities: Property and equipment (673 ) (370 ) Total gross deferred tax liabilities (673 ) (370 ) Net deferred tax assets $ 185,914 $ 313,207 As of December 27, 2017 , our federal and state net operating loss carryforwards for income tax purposes were $51,668 and $19,166 . If not utilized, our federal and state net operating loss carryforwards will begin to expire in 2035. As described in Note 11, we acquired an aggregate of 1,376,093 LLC Interests during fiscal 2017 through redemptions of LLC Interests and the exercise of employee stock options. We recognized a deferred tax asset in the amount of $14,370 associated with the basis difference in our investment in SSE Holdings upon acquiring these LLC Interests. These were partially offset by reductions in basis due to the utilization of $14,339 of amortization. However, a portion of the total basis difference will only reverse upon the eventual sale of our interest in SSE Holdings, which we expect would result in a capital loss. As of December 27, 2017 , we established a valuation allowance in the amount of $10,114 against the deferred tax asset to which this portion relates. During fiscal 2017 , we also recognized $7,661 of deferred tax assets related to additional tax basis increases generated from expected future payments under the Tax Receivable Agreement and related deductions for imputed interest on such payments. See "—Tax Receivable Agreement" for more information. We evaluate the realizability of our deferred tax assets on a quarterly basis and establish valuation allowances when it is more likely than not that all or a portion of a deferred tax asset may not be realized. As of December 27, 2017 , we concluded, based on the weight of all available positive and negative evidence, that all of our deferred tax assets (except for those deferred tax assets described above relating to basis differences that are expected to result in a capital loss upon the eventual sale of our interest in SSE Holdings) are more likely than not to be realized. As such, no additional valuation allowance was recognized. The net change in valuation allowance for fiscal 2017 was a decrease of $5,454 . Uncertain Tax Positions There were no reserves for uncertain tax positions as of December 27, 2017 and December 28, 2016 . Shake Shack Inc. was formed in September 2014 and did not engage in any operations prior to the IPO and Organizational Transactions. Shake Shack Inc. first filed tax returns for tax year 2014, which is the first tax year subject to examination by taxing authorities for U.S. federal and state income tax purposes. Additionally, although SSE Holdings is treated as a partnership for U.S. federal and state income taxes purposes, it is still required to file an annual U.S. Return of Partnership Income, which is subject to examination by the Internal Revenue Service ("IRS"). The statute of limitations has expired for tax years through 2013 for SSE Holdings. Tax Receivable Agreement Pursuant to our election under Section 754 of the Internal Revenue Code (the "Code"), we expect to obtain an increase in our share of the tax basis in the net assets of SSE Holdings when LLC Interests are redeemed or exchanged by the non-controlling interest holders and other qualifying transactions. We plan to make an election under Section 754 of Code for each taxable year in which a redemption or exchange of LLC Interest occurs. We intend to treat any redemptions and exchanges of LLC Interests by the non-controlling interest holders as direct purchases of LLC Interests for U.S. federal income tax purposes. These increases in tax basis may reduce the amounts that we would otherwise pay in the future to various tax authorities. They may also decrease gains (or increase losses) on future dispositions of certain capital assets to the extent tax basis is allocated to those capital assets. On February 4, 2015, we entered into a tax receivable agreement with the then-existing non-controlling interest holders (the "Tax Receivable Agreement") that provides for the payment by us to the non-controlling interest holders of 85% of the amount of any tax benefits that we actually realize, or in some cases are deemed to realize, as a result of (i) increases in our share of the tax basis in the net assets of SSE Holdings resulting from any redemptions or exchanges of LLC Interests, (ii) tax basis increases attributable to payments made under the Tax Receivable Agreement, and (iii) deductions attributable to imputed interest pursuant to the Tax Receivable Agreement (the "TRA Payments"). We expect to benefit from the remaining 15% of any tax benefits that we may actually realize. The TRA Payments are not conditioned upon any continued ownership interest in SSE Holdings or us. The rights of each non-controlling interest holder under the Tax Receivable Agreement are assignable to transferees of its LLC Interests. During fiscal 2017 , we acquired an aggregate of 1,003,585 LLC Interests in connection with the redemption of LLC Interests, which resulted in an increase in the tax basis of our investment in SSE Holdings subject to the provisions of the Tax Receivable Agreement. We recognized an additional liability in the amount of $18,973 for the TRA Payments due to the redeeming members, representing 85% of the aggregate tax benefits we expect to realize from the tax basis increases related to the redemption of LLC Interests, after concluding it was probable that such TRA Payments would be paid based on our estimates of future taxable income. Also, we r ecognized $125,859 benefit in other income related to the reduction in liabilities under its Tax Receivable Agreement related to the enactment of the TCJA. During fiscal 2017 payments of $4,910 , inclusive of interest, were made to members of SSE Holdings pursuant to the Tax Receivable Agreement. As of December 27, 2017 , the total amount of TRA Payments due under the Tax Receivable Agreement was $159,373 , of which $937 was included in other current liabilities on the Consolidated Balance Sheet. See Note 17 for more information relating to our liabilities under the Tax Receivable Agreement.

EARNINGS PER SHARE

EARNINGS PER SHARE	12 Months Ended
	Dec. 27, 2017
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE Basic earnings per share of Class A common stock is computed by dividing net income attributable to Shake Shack Inc. by the weighted-average number of shares of Class A common stock outstanding during the period. Diluted earnings per share of Class A common stock is computed by dividing net income attributable to Shake Shack Inc. by the weighted-average number of shares of Class A common stock outstanding adjusted to give effect to potentially dilutive securities. The following table sets forth reconciliations of the numerators and denominators used to compute basic and diluted earnings per share of Class A common stock for fiscal 2017 , 2016 and 2015 . 2017 2016 2015 Numerator: Net income $ 8,884 $ 22,146 $ 3,124 Less: net income attributable to non-controlling interests 9,204 9,700 11,900 Net income (loss) attributable to Shake Shack Inc. $ (320 ) $ 12,446 $ (8,776 ) Denominator: Weighted-average shares of Class A common stock outstanding—basic 25,876 22,956 13,588 Effect of dilutive securities: Stock options — 493 — Weighted-average shares of Class A common stock outstanding—diluted 25,876 23,449 13,588 Earnings (loss) per share of Class A common stock—basic $ (0.01 ) $ 0.54 $ (0.65 ) Earnings (loss) per share of Class A common stock—diluted $ (0.01 ) $ 0.53 $ (0.65 ) Shares of our Class B common stock do not share in the earnings or losses of Shake Shack and are therefore not participating securities. As such, separate presentation of basic and diluted earnings per share of Class B common stock under the two-class method has not been presented. The following table presents potentially dilutive securities excluded from the computations of diluted earnings per share of Class A common stock for fiscal 2017 , 2016 and 2015 . 2017 2016 2015 Stock options (1) 1,719,341 (3) 125 (2) 2,574,981 (3) Performance stock units (1) 124,842 (3) 26,860 (4) — Restricted stock units (1) 44,476 (3) — — Shares of Class B common stock 10,250,007 (5) 11,253,592 (5) 16,460,741 (5) (1) Represents the number of instruments outstanding at the end of the period. Application of the treasury stock method would reduce this amount if they had a dilutive effect and were included in the computation of diluted earnings per share. (2) Excluded from the computation of diluted earnings per share of Class A common stock because the exercise price of the stock options exceeded the average market price of our Class A common stock during the period ("out-of-the-money"). (3) Excluded from the computation of diluted earnings per share of Class A common stock because the effect would have been anti-dilutive. (4) Weighted-average number of securities excluded from the computation of diluted earnings per share of Class A common stock because the performance conditions were not met for a portion of the fiscal year. (5) Shares of our Class B common stock are considered potentially dilutive shares of Class A common stock. Amounts have been excluded from the computations of diluted earnings per share of Class A common stock because the effect would have been anti-dilutive under the if-converted and two-class methods.

SUPPLEMENTAL CASH FLOW INFORMAT

SUPPLEMENTAL CASH FLOW INFORMATION	12 Months Ended
	Dec. 27, 2017
Supplemental Cash Flow Elements [Abstract]
SUPPLEMENTAL CASH FLOW INFORMATION	SUPPLEMENTAL CASH FLOW INFORMATION The following table sets forth supplemental cash flow information for fiscal 2017 , 2016 and 2015 : 2017 2016 2015 Cash paid for: Income taxes, net of refunds $ 2,261 $ 1,823 $ 416 Interest, net of amounts capitalized 1,106 54 92 Non-cash investing activities: Accrued purchases of property and equipment 7,526 6,150 4,904 Capitalized landlord assets for leases where we are deemed the accounting owner 10,125 1,985 — Capitalized equity-based compensation 109 139 — Class A common stock issued in connection with the acquisition of the former indirect members of SSE Holdings — — 6 Class A common stock issued in connection with the USC Merger — — 2 Non-cash financing activities: Cancellation of Class B common stock in connection with the Organizational Transactions — — (6 ) Class A common stock issued in connection with the redemption of LLC Interests 1 5 6 Cancellation of Class B common stock in connection with the redemption of LLC Interests (1 ) (5 ) (6 ) Cancellation of Class B common stock in connection with the USC Merger — — (2 ) Establishment of liabilities under tax receivable agreement 18,973 100,063 173,090 Accrued distributions payable to non-controlling interest holders — 607 —

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 27, 2017
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Lease Commitments We are obligated under various operating leases for Shacks and our home office space, expiring in various years through 2035 . Under certain of these leases, we are liable for contingent rent based on a percentage of sales in excess of specified thresholds and are responsible for our proportionate share of real estate taxes, common area maintenance charges and utilities. See Note 9 , Leases. As security under the terms of several of our leases, we are obligated under letters of credit totaling $160 as of December 27, 2017 . The letters of credit expire on April 23, 2018 and February 28, 2026 . In addition, in December 2013, we entered into an irrevocable standby letter of credit in conjunction with our home office lease in the amount of $80 . The letter of credit expires in September 2018 and renews automatically for one -year periods through September 30, 2019 . In September 2017, we entered into an irrevocable standby letter of credit in conjunction with our new home office lease in the amount of $603 . The letter of credit expires in August 2018 and renews automatically for one-year periods through January 31, 2034 . Purchase Commitments Purchase obligations include legally binding contracts, including commitments for the purchase, construction or remodeling of real estate and facilities, firm minimum commitments for inventory purchases, equipment purchases, marketing-related contracts, software acquisition/license commitments and service contracts. These obligations are generally short-term in nature and are recorded as liabilities when the related goods are received or services rendered. We also enter into long-term, exclusive contracts with certain vendors to supply us with food, beverages and paper goods, obligating us to purchase specified quantities. These volume commitments are generally not subject to any time limit and there are no material financial penalties associated with these agreements in the event of early termination. Legal Contingencies In November 2015, we participated in a voluntary mediation with counsel representing two former Shake Shack managers, who alleged that we improperly classified our restaurant managers as exempt from overtime protections. At the conclusion of the mediation, the parties mutually agreed to fully and finally resolve the matter by settling, rather than litigating. In connection with the settlement, the parties entered into a memorandum of understanding, pursuant to which we agreed to create a settlement fund in the amount of $750 and, in exchange for their participation in the settlement fund, all participating employees (current and former) were required to release Shake Shack from all federal and/or state wage and hour claims that may exist through the settlement date. On March 11, 2016, as required by the memorandum of understanding, the parties entered into a settlement agreement in the amount of $750 . To facilitate the resolution of the matter, the parties coordinated the filing by the plaintiff's counsel of a Complaint on March 17, 2016 with the Supreme Court of the State of New York (the “Court”). On October 25, 2016, the Court granted preliminary approval of the settlement agreement. On December 13, 2016, all eligible class members were mailed the notice of settlement, and the deadline to opt-out or object was January 27, 2017. On March 7, 2017, the Court held a fairness hearing, at which time it determined that the settlement agreement was fair, adequate and equitable, and subsequently issued its order granting final approval of the settlement. On May 1, 2017, we paid to the claims administrator $774 in full satisfaction of the amounts owed by us under the settlement agreement and related expenses. We are subject to various legal proceedings, claims and liabilities, such as employment-related claims and slip and fall cases, which arise in the ordinary course of business and are generally covered by insurance. As of December 27, 2017 , the amount of ultimate liability with respect to these matters was not material. Liabilities under Tax Receivable Agreement As described in Note 14, we are a party to the Tax Receivable Agreement under which we are contractually committed to pay the non-controlling interest holders 85% of the amount of any tax benefits that we actually realize, or in some cases are deemed to realize, as a result of certain transactions. We are not obligated to make any payments under the Tax Receivable Agreement until the tax benefits associated the transaction that gave rise to the payment are realized. Amounts payable under the Tax Receivable Agreement are contingent upon, among other things, (i) generation of future taxable income over the term of the Tax Receivable Agreement and (ii) future changes in tax laws. If we do not generate sufficient taxable income in the aggregate over the term of the Tax Receivable Agreement to utilize the tax benefits, then we would not be required to make the related TRA Payments. As of December 27, 2017 , we recognized $159,373 of liabilities relating to our obligations under the Tax Receivable Agreement, after concluding that it was probable that we would have sufficient future taxable income to utilize the related tax benefits. There were no transactions subject to the Tax Receivable Agreement for which we did not recognize the related liability, as we concluded that we would have sufficient future taxable income to utilize all of the related tax benefits generated by all transactions that occurred in fiscal 2017 .

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	12 Months Ended
	Dec. 27, 2017
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS Union Square Hospitality Group The Chairman of our Board of Directors serves as the Chief Executive Officer of Union Square Hospitality Group, LLC. As a result, Union Square Hospitality Group, LLC and its subsidiaries are considered related parties. USHG, LLC Effective January 2015, we entered into an Amended and Restated Management Services Agreement with USHG, LLC ("USHG"), which USHG provides reduced management services to SSE Holdings comprised of executive leadership from members of its senior management, advisory and development services and limited leadership development and human resources services. The initial term of the Amended and Restated Management Services Agreement is through December 31, 2019, with renewal periods. Total amounts paid to USHG for general corporate expenses were $7 , $10 and $157 for fiscal 2017 , 2016 and 2015 , respectively, and are included in general and administrative expenses on the Consolidated Statements of Income (Loss) . Previously, our employees were included in USHG's self-insurance health plan and we paid our portion of the plan costs on a monthly basis to USHG. In February 2015, we established our own self-funded health insurance plan for our employees and ceased payments to USHG. Amounts paid to USHG for these health insurance costs were $146 for fiscal 2015 . No amounts were paid to USHG for these health insurance costs for fiscal 2017 and 2016 . This amount is included in labor and related expenses and general and administrative expenses on the Consolidated Statements of Income (Loss) . Additionally, our employees are eligible participants under USHG's 401(k) plan. We pay our share of the employer's matching contributions directly to the third-party plan trustee. No amounts were payable to USHG as of December 27, 2017 . Total amounts payable to USHG as of December 28, 2016 were $1 , which is included in other current liabilities on the Consolidated Balance Sheets. No amounts were due from USHG as of December 27, 2017 and December 28, 2016 . Daily Provisions For a period of time in fiscal 2017, we purchased coffee cake from the restaurant Daily Provisions to offer as a breakfast item at our Madison Square Park Shack. Amounts paid to Daily Provisions for fiscal 2017 were $6 . No amounts were payable to Daily Provisions as of December 27, 2017 and December 28, 2016 . Hudson Yards Sports and Entertainment In fiscal 2011, we entered into a Master License Agreement (as amended, an "MLA") with Hudson Yards Sports and Entertainment LLC ("HYSE") to operate Shake Shack branded limited menu concession stands in sports and entertainment venues within the United States. The agreement expires on December 31, 2027 and includes five consecutive five -year renewal options at HYSE's option. As consideration for these rights, HYSE pays us a license fee based on a percentage of net food sales, as defined in the MLA. HYSE also pays us a percentage of profits on sales of branded beverages, as defined in the MLA. Amounts paid to us by HYSE for fiscal 2017 , 2016 and 2015 were $452 , $309 and $282 , respectively, and are included in licensing revenue on the Consolidated Statements of Income (Loss) . Total amounts due from HYSE as of December 27, 2017 and December 28, 2016 were $18 and $11 , respectively, which are included in p repaid expenses and other current assets on the Consolidated Balance Sheets . Madison Square Park Conservancy The Chairman of our Board of Directors serves as a director of the Madison Square Park Conservancy ("MSP Conservancy"), with which we have a license agreement and pay license fees to operate our Madison Square Park Shack. Amounts paid to Madison Square Park Conservancy as rent amounted to $907 , $1,062 and $692 for f iscal 2017 , 2016 and 2015 , respectively. These amounts are included in occupancy and related expenses on the Consolidated Statements of Income (Loss) . No amounts were due to MSP Conservancy as of December 27, 2017 . Total amounts due to MSP Conservancy were were $1 as of December 28, 2016 , which is included in accrued expenses on the Consolidated Balance Sheets. Additionally, we received tenant improvement allowances from MSP Conservancy related to a reconstruction project which ended in 2015. Amounts paid to us from MSP Conservancy for fiscal 2017 were $200 . No amounts were paid to us by MSP Conservancy in fiscal 2016 and 2015 . No amounts were due to us from MSP Conservancy as of December 27, 2017. Total amounts due from MSP Conservancy as of December 28, 2016 were $200 , which is included in account receivable on the Consolidated Balance Sheets. Share Our Strength The Chairman of our Board of Directors serves as a director of Share Our Strength, for which Shake Shack holds the "Great American Shake Sale" every year during the month of May to raise money and awareness for childhood hunger. During the Great American Shake Sale, we encourage guests to donate money to Share Our Strength's No Kid Hungry campaign in exchange for a coupon for a free cake-themed shake. All of the guest donations we collect go directly to Share Our Strength. We raised a total of $633 , $587 and $504 in fiscal 2017 , 2016 and 2015 , respectively, and the proceeds were remitted to Share Our Strength in the respective years. We incurred costs of approximately $148 , $117 and $109 for fiscal 2017 , 2016 and 2015 , respectively, representing the cost of the free shakes redeemed. These costs are included in general and administrative expenses and other operating expenses on the Consolidated Statements of Income (Loss) . Additionally, we held a promotional event in August 2016 in which we donated a total of $20 to the Share Our Strength's No Kid Hungry campaign, which is included in general and administrative expenses on the Consolidated Statements of Income (Loss) . Mobo Systems, Inc. The Chairman of our Board of Directors serves as a director of Mobo Systems, Inc. (also known as "Olo"), a platform we use in connection with our mobile ordering application. Amounts paid to Olo for fiscal 2017 and 2015 were $80 and $8 , respectively, which are included in other operating expenses on the Consolidated Statements of Income (Loss) . No amounts were paid to Olo for fiscal 2016 . No amounts were payable to Olo as of December 27, 2017 and December 28, 2016 . Square, Inc. In July 2017, our Chief Executive Officer joined the Board of Directors of Square, Inc. ("Square"). We currently use certain point-of-sale applications, payment processing services, hardware and other enterprise platform services in connection with the processing of a limited amount of sales at certain of our Shacks, sales for certain off-site events and in connection with our kiosk technology. Additionally, in March 2017 and October 2017, we partnered with Caviar, Square's food ordering service, for a limited-time delivery promotion. Amounts paid to Square for fiscal 2017 were $33 which are included in other operating expenses on the Consolidated Statements of Income (Loss) . No amounts were payable to Square as of December 27, 2017 and December 28, 2016 . Tax Receivable Agreement In connection with our IPO, we entered into a Tax Receivable Agreement with certain non-controlling interest holders that provides for the payment by us to the non-controlling holders of 85% of the amount of any tax benefits that Shake Shack actually realizes or in some cases is deemed to realize as a result of (i) increases in the tax basis of the net assets of SSE Holdings resulting from any redemptions or exchanges of LLC Interests and (ii) certain other tax benefits related to our making payments under the Tax Receivable Agreement. See Note 14 for further information. In fiscal 2017, payments of $4,910 , inclusive of interest, were made to the non-controlling interest holders. There were no amounts paid under the Tax Receivable Agreement to the non-controlling interest holders during fiscal 2016 and 2015 . As of December 27, 2017 and December 28, 2016 , total amounts due under the Tax Receivable Agreement were $159,373 and $272,482 , respectively. Distributions to Members of SSE Holdings Under the terms of the SSE Holdings LLC Agreement, SSE Holdings is obligated to make tax distributions to its members. During fiscal 2017 and 2016 tax distributions of $2,379 and $1,745 , respectively, were paid to non-controlling interest holders. A special distribution was paid to certain members of SSE Holdings in the amount of $11,125 on February 4, 2015. No tax distributions were paid to non-controlling interest holders during fiscal 2015 . No tax distributions were payable to non-controlling interest holders as of December 27, 2017 . As of December 28, 2016 , $607 was payable to non-controlling interest holders.

GEOGRAPHIC INFORMATION

GEOGRAPHIC INFORMATION	12 Months Ended
	Dec. 27, 2017
Segment Reporting [Abstract]
GEOGRAPHIC INFORMATION	GEOGRAPHIC INFORMATION Revenue by geographic area for fiscal 2017 , 2016 and 2015 is as follows: 2017 2016 2015 United States $ 348,575 $ 260,602 $ 184,408 Other countries 10,235 7,873 6,184 Total revenue $ 358,810 $ 268,475 $ 190,592 Revenues are shown based on the geographic location of our customers and licensees. All of our assets are located in the United States.

SELECTED QUARTERLY FINANCIAL DA

SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)	12 Months Ended
	Dec. 27, 2017
Quarterly Financial Information Disclosure [Abstract]
SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)	SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) The following table sets forth certain unaudited financial information for each quarter of fiscal 2017 and 2016 . The unaudited quarterly information includes all adjustments (consisting of normal recurring adjustments) that, in the opinion of management, are necessary for the fair presentation of the information presented. Operating results for interim periods are not necessarily indicative of the results that may be expected for a full fiscal year. 2017 First Second Third Fourth Quarter Quarter Quarter Quarter Total revenue $ 76,749 $ 91,316 $ 94,609 $ 96,136 Operating income 5,628 11,737 10,610 5,838 Net income (loss) 3,862 8,184 7,870 (11,032 ) Net income (loss) attributable to Shake Shack Inc. 2,267 4,879 4,997 (12,463 ) Earnings (loss) per share (1) : Basic $ 0.09 $ 0.19 $ 0.19 $ (0.47 ) Diluted $ 0.09 $ 0.19 $ 0.19 $ (0.47 ) 2016 First Second Third Fourth Quarter Quarter Quarter Quarter Total revenue $ 54,165 $ 66,472 $ 74,567 $ 73,271 Operating income 4,714 8,933 9,170 4,988 Net income 3,351 6,549 6,789 5,457 Net income attributable to Shake Shack Inc. 1,462 3,298 3,766 3,920 Earnings per share (1) : Basic $ 0.07 $ 0.15 $ 0.16 $ 0.16 Diluted $ 0.07 $ 0.14 $ 0.15 $ 0.15 (1) Basic and diluted earnings per share are computed independently for each of the quarters presented. Therefore, the sum of quarterly basic and diluted earnings per share amounts may not equal annual basic and diluted earnings per share amounts.

SCHEDULE I_ CONDENSED FINANCIAL

SCHEDULE I: CONDENSED FINANCIAL INFORMATION OF REGISTRANT	12 Months Ended
	Dec. 27, 2017
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
SCHEDULE I: CONDENSED FINANCIAL INFORMATION OF REGISTRANT	SHAKE SHACK INC. CONDENSED BALANCE SHEETS (PARENT COMPANY ONLY) (in thousands, except share and per share amounts) December 27 December 28 ASSETS Current assets: Cash $ 4,988 $ 3,785 Accounts receivable — 2 Prepaid expenses 100 105 Total current assets 5,088 3,892 Deferred income taxes, net 185,750 312,802 Investment in subsidiaries 142,314 109,680 TOTAL ASSETS $ 333,152 $ 426,374 LIABILITIES AND STOCKHOLDERS' EQUITY Current liabilities: Accrued expenses 70 49 Due to SSE Holdings 4,217 1,655 Current portion of liabilities under tax receivable agreement 937 4,580 Total current liabilities 5,224 6,284 Liabilities under tax receivable agreement, net of current portion 158,436 267,902 Total liabilities 163,660 274,186 Commitments and contingencies Stockholders' equity: Preferred stock, no par value—10,000,000 shares authorized; none issued and outstanding as of December 27, 2017 and December 28, 2016, respectively. — — Class A common stock, $0.001 par value—200,000,000 shares authorized; 26,527,477 and 25,151,384 shares issued and outstanding as of December 27, 2017 and December 28, 2016, respectively. 27 25 Class B common stock, $0.001 par value—35,000,000 shares authorized; 10,250,007 and 11,253,592 shares issued and outstanding as of December 27, 2017 and December 28, 2016, respectively. 10 11 Additional paid-in capital 153,105 135,448 Retained earnings 16,399 16,719 Accumulated other comprehensive loss (49 ) (15 ) Total stockholders' equity 169,492 152,188 TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY $ 333,152 $ 426,374 See accompanying Notes to Condensed Financial Statements. SHAKE SHACK INC. CONDENSED STATEMENTS OF INCOME (LOSS) (PARENT COMPANY ONLY) (in thousands) Fiscal Year Ended December 27 December 28 December 30 Intercompany revenue $ 1,466 $ 1,603 $ 1,336 TOTAL REVENUE 1,466 1,603 1,336 General and administrative expenses 1,692 1,603 1,336 TOTAL EXPENSES 1,692 1,603 1,336 OPERATING LOSS (226 ) — — Equity in net income of subsidiaries 22,090 16,982 6,906 Other income 127,221 688 — Interest expense (50 ) (16 ) — INCOME BEFORE INCOME TAXES 149,035 17,654 6,906 Income tax expense 149,355 5,208 2,633 NET INCOME (LOSS) $ (320 ) $ 12,446 $ 4,273 See accompanying Notes to Condensed Financial Statements. SHAKE SHACK INC. CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (PARENT COMPANY ONLY) (in thousands) Fiscal Year Ended December 27 December 28 December 30 Net income (loss) $ (320 ) $ 12,446 $ 4,273 Other comprehensive (loss), net of tax: Available-for-sale securities (1) : Change in net unrealized holding (losses) (67 ) (22 ) (5 ) Less: reclassification adjustments for net realized losses included in net income 33 12 — Net change (34 ) (10 ) (5 ) OTHER COMPREHENSIVE LOSS (34 ) (10 ) (5 ) COMPREHENSIVE INCOME (LOSS) $ (354 ) $ 12,436 $ 4,268 (1) Net of tax benefit of $0 for fiscal years ended December 27, 2017 , December 28, 2016 and December 30, 2015 . See accompanying Notes to Condensed Financial Statements. SHAKE SHACK INC. CONDENSED STATEMENTS OF CASH FLOWS (PARENT COMPANY ONLY) (in thousands) Fiscal Year Ended December 27 December 28 December 30 OPERATING ACTIVITIES Net income (loss) $ (320 ) $ 12,446 $ 4,273 Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities: Equity in net income of subsidiaries (22,090 ) (16,982 ) (6,906 ) Equity-based compensation 234 189 330 Non-cash reimbursement revenue treated as investment — (189 ) — Deferred income taxes 146,095 (462 ) (551 ) Other non-cash income (127,221 ) (688 ) — Changes in operating assets and liabilities: Accounts receivable 2 (2 ) — Prepaid expenses and other current assets 5 (1 ) — Due to/from SSE Holdings (5,339 ) 214 4 Accrued expenses 21 (11 ) 58 Other current liabilities (17 ) 17 — Income taxes payable 2,990 5,023 3,184 NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES (5,640 ) (446 ) 392 INVESTING ACTIVITIES Purchases of LLC Interests from SSE Holdings (5,522 ) (4,559 ) (112,298 ) Return of investment in SSE Holdings 4,101 2,694 — NET CASH USED IN INVESTING ACTIVITIES (1,421 ) (1,865 ) (112,298 ) FINANCING ACTIVITIES Proceeds from issuance of Class A common stock sold in initial public offering, net of underwriting discounts and commissions — — 112,298 Proceeds from issuance of Class A common stock to SSE Holdings upon settlement of stock option exercises 5,522 2,489 — Proceeds from issuance of Class B common stock — — 30 Proceeds from stock option exercises 7,586 3,185 — Payments under tax receivable agreement (4,844 ) — — NET CASH PROVIDED BY FINANCING ACTIVITIES 8,264 5,674 112,328 INCREASE IN CASH 1,203 3,363 422 CASH AT BEGINNING OF PERIOD 3,785 422 — CASH AT END OF PERIOD $ 4,988 $ 3,785 $ 422 See accompanying Notes to Condensed Financial Statements. NOTE 1: ORGANIZATION Sha ke Shack Inc. (the "Parent Company") was formed on September 23, 2014 as a Delaware corporation and is a holding company with no direct operations. The Parent Company's assets consist primarily of its equity interest in SSE Holdings, LLC ("SSE Holdings") and certain deferred tax assets. On February 4, 2015, the Parent Company completed an initial public offering ("IPO") of 5,750,000 shares of its Class A common stock at a public offering price of $21.00 per share, which includes 750,000 shares issued pursuant to the underwriters' over-allotment option. The Parent Company received $112,298 in proceeds, net of underwriting discounts and commissions, which it used to purchase newly-issued membership interests from SSE Holdings at a price per interest equal to the initial public offering price of its Class A common stock. The Parent Company's cash inflows are primarily from cash dividends or distributions and other transfers from SSE Holdings. The amounts available to the Parent Company to fulfill cash commitments and pay cash dividends on its common stock are subject to certain restrictions in SSE Holdings' revolving credit agreement. See Note 8 to the consolidated financial statements. NOTE 2: BASIS OF PRESENTATION These condensed parent company financial statements should be read in conjunction with the consolidated financial statements of Shake Shack Inc. and the accompanying notes thereto, included in this Annual Report on Form 10-K. For purposes of these condensed financial statements, the Parent Company's interest in SSE Holdings is recorded based upon its proportionate share of SSE Holdings' net assets (similar to presenting them on the equity method). The Parent Company is the sole managing member of SSE Holdings, and pursuant to the Third Amended and Restated LLC Agreement of SSE Holdings (the “SSE Holdings LLC Agreement”), receives compensation in the form of reimbursements for all costs associated with being a public company and maintaining its existence. Intercompany revenue consists of these reimbursement payments and is recognized when the corresponding expense to which it relates is recognized. Certain intercompany balances presented in these condensed parent company financial statements are eliminated in the consolidated financial statements. As of December 27, 2017 , $4,217 of intercompany payables were eliminated in consolidation and $1,655 of intercompany payables were eliminated in consolidation as of December 28, 2016 . For fiscal 2017 , $1,466 and $22,090 of intercompany revenue and equity in net income of subsidiaries, respectively, was eliminated in consolidation. For fiscal 2016 , $1,603 and $16,982 of intercompany revenue and equity in net income of subsidiaries, respectively, was eliminated in consolidation. Related party amounts that were not eliminated in the consolidated financial statements include the Parent Company's liabilities under the tax receivable agreement, which totaled $159,373 and $272,482 as of December 27, 2017 and December 28, 2016 , respectively. NOTE 3: COMMITMENTS AND CONTINGENCIES On February 4, 2015, the Parent Company entered into a tax receivable agreement with the non-controlling interest holders that provides for payments to the non-controlling interest holders of 85% of the amount of any tax benefits that the Parent Company actually realizes, or in some cases is deemed to realize, as a result of certain transactions. S ee Note 14 to the consolidated financial statements for more information regarding the Parent Company's tax receivable agreement. As described in Note 17 to the consolidated financial statements, a mounts payable under the tax receivable agreement are contingent upon, among other things, (i) generation of future taxable income of Shake Shack Inc. over the term of the tax receivable agreement and (ii) future changes in tax laws. In December 2017, the Tax Cuts and Jobs Act of 2017 (the "TCJA") was enacted into law. The TCJA provides for significant changes to the U.S. Internal Revenue Code of 1986, as amended, including the reduction of the U.S. federal corporate income tax rate from 35% to 21%, among other provisions. As a result of the TCJA, we recognized a $125,859 benefit in other income related to the reduction in liabilities under its tax receivable agreement. As of December 27, 2017 and December 28, 2016 , liabilities under the tax receivable agreement totaled $159,373 and $272,482 , respectively. NOTE 4: SUPPLEMENTAL CASH FLOW INFORMATION The following table sets forth supplemental cash flow information for fiscal 2017 , 2016 and 2015 : 2017 2016 2015 Cash paid for: Income taxes $ 253 $ 576 $ — Interest 2 — — Non-cash investing activities: Accrued contribution related to stock option exercises 7,586 1,116 — Class A common stock issued in connection with the acquisition of two entities owned by former indirect members of SSE Holdings — — 6 Class A common stock issued in connection with the USC Merger — — 2 Class A common stock issued in connection with the acquisition of LLC Interests upon redemption by the non-controlling interest holders 4,415 18,944 19,933 Non-cash contribution made in connection with equity awards granted to employees of SSE Holdings 5,497 5,304 2,355 Non-cash financing activities: Cancellation of Class B common stock in connection with the Organizational Transactions — — (6 ) Cancellation of Class B common stock in connection with the redemption of LLC Interests (1 ) (5 ) (6 ) Cancellation of Class B common stock in connection with the USC Merger — — (2 ) Establishment of liabilities under tax receivable agreement 18,973 100,063 173,090

SCHEDULE II_ VALUATION AND QUAL

SCHEDULE II: VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Dec. 27, 2017
Valuation and Qualifying Accounts [Abstract]
SCHEDULE II: VALUATION AND QUALIFYING ACCOUNTS	Schedule II: Valuation and Qualifying Accounts Balance at beginning of period Additions Reductions Balance at end of period (in thousands) Charged to costs and expenses Charged to other accounts Deferred tax asset valuation allowance: Fiscal year ended December 31, 2014 $ — $ — $ — $ — $ — Fiscal year ended December 30, 2015 $ — $ — $ 39,700 (1) $ (16,545 ) $ 23,155 Fiscal year ended December 28, 2016 $ 23,155 $ 90 $ 1,965 (1) $ (9,642 ) $ 15,568 Fiscal year ended December 27, 2017 $ 15,568 $ — $ 3,455 (1) $ (8,909 ) (2) $ 10,114 (1) Amount relates to a valuation allowance established on deferred tax assets related to our investment in SSE Holdings. (2) Amount includes a $4,780 remeasurement adjustment related to the enactment of the TCJA, which was recognized through earnings.

SUMMARY OF SIGNIFICANT ACCOUN31

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 27, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and include our accounts and the accounts of our subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior period amounts to conform to the current year presentation. SSE Holdings is considered a variable interest entity. Shake Shack Inc. is the primary beneficiary as we have the majority economic interest in SSE Holdings and, as the sole managing member, have decision making authority that significantly affects the economic performance of the entity, while the limited partners have no substantive kick-out or participating rights. As a result, we will continue to consolidate SSE Holdings. The assets and liabilities of SSE Holdings represent substantially all of our consolidated assets and liabilities with the exception of certain deferred taxes and liabilities under the Tax Receivable Agreement. As of December 27, 2017 and December 28, 2016 , the net assets of SSE Holdings were $197,301 and $158,845 , respectively. The assets of SSE Holdings are subject to certain restrictions in SSE Holdings' revolving credit agreements. See Note 8 for more information.
Fiscal Year	Fiscal Year We operate on a 52/53 week fiscal year ending on the last Wednesday in December. Fiscal year 2017 contained 52 weeks and ended on December 27, 2017 . Fiscal year 2016 contained 52 weeks and ended on December 28, 2016 . Fiscal year 2015 contained 52 weeks and ended on December 30, 2015 . Unless otherwise stated, references to years in this report relate to fiscal years.
Use of Estimates	Use of Estimates The preparation of these consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of sales and expenses during the reporting period. Actual results could differ from those estimates.
Segment Reporting	Segment Reporting We own and operate Shacks in the United States. We also have domestic and international licensed operations. Our chief operating decision maker (the "CODM") is our Chief Executive Officer. As the CODM reviews financial performance and allocates resources at a consolidated level on a recurring basis, we have one operating segment and one reportable segment.
Fair Value Measurements	Fair Value Measurements We apply fair value accounting for all financial assets and liabilities and non-financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis. Fair value is defined as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities that are required to be recorded at fair value, we assume the highest and best use of the asset by market participants in which we would transact and the market-based risk measurements or assumptions that market participants would use in pricing the asset or liability, such as inherent risk, transfer restrictions, and credit risk. Assets and liabilities are classified using a fair value hierarchy, which prioritizes the inputs used to measure fair value into three levels, and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: ▪ Level 1 - Quoted prices in active markets for identical assets or liabilities ▪ Level 2 - Observable inputs other than quoted prices in active markets for identical assets or liabilities, quoted prices for identical assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities ▪ Level 3 - Inputs that are both unobservable and significant to the overall fair value measurements reflecting an entity's estimates of assumptions that market participants would use in pricing the asset or liability
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consist primarily of cash on hand, deposits with banks, and short-term, highly liquid investments that have original maturities of three months or less. Cash equivalents are stated at cost, which approximates fair value. Cash equivalents consist primarily of money market funds.
Accounts Receivable	Accounts Receivable Accounts receivable consist primarily of receivables from landlords for tenant improvement allowances, receivables from our licensees for licensing revenue and related reimbursements, credit card receivables and vendor rebates. We evaluate the collectibility of our accounts receivable based on a variety of factors, including historical experience, current economic conditions and other factors.
Inventories	Inventories Inventories, which consist of food, beer, wine, other beverages and retail merchandise, are stated at the lower of cost or net realizable value with cost determined on a first-in, first-out basis. No adjustment is deemed necessary to reduce inventory to net realizable value due to the rapid turnover and high utilization of inventory.
Property and Equipment	Property and Equipment Property and equipment is stated at historical cost less accumulated depreciation. Property and equipment is depreciated based on the straight-line method over the estimated useful lives of the assets, generally ranging from three to seven years for equipment, furniture and fixtures, and computer equipment and software. Leasehold improvements are depreciated over the shorter of their estimated useful life or the related lease life, generally ranging from 10 to 15 years. Landlord funded assets are depreciated over the shorter of their estimated useful life or the related lease life, generally ranging from 10 to 15 years. For leases with renewal periods at our option, we use the original lease term, excluding renewal option periods, to determine estimated useful lives. Costs incurred when constructing Shacks are capitalized. The cost of repairs and maintenance are expensed when incurred. Costs for refurbishments and improvements that significantly increase the productive capacity or extend the useful life of the asset are capitalized. When assets are disposed of, the resulting gain or loss is recognized on the Consolidated Statements of Income (Loss). We assess potential impairments to our long-lived assets, which includes property and equipment, whenever events or circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of an asset is measured by a comparison of the carrying amount of an asset group to its estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of the asset group exceeds its estimated undiscounted future cash flows, an impairment charge is recognized as the amount by which the carrying amount of the asset exceeds the fair value of the asset.
Deferred Financing Costs	Deferred Financing Costs Deferred financing costs incurred in connection with the issuance of long-term debt and establishing credit facilities are capitalized and amortized to interest expense based on the related debt agreements. Deferred financing costs are included in other assets on the Consolidated Balance Sheets.
Other Assets	Other Assets Other assets consist primarily of long-term marketable securities, security deposits, transferable liquor licenses and certain custom furniture pre-ordered for future Shacks and yet to be placed in service. The costs of obtaining non-transferable liquor licenses that are directly issued by local government agencies for nominal fees are expensed as incurred. The costs of purchasing transferable liquor licenses through open markets in jurisdictions with a limited number of authorized liquor licenses are capitalized as indefinite-lived intangible assets. Annual liquor license renewal fees are expensed over the renewal term. As of December 27, 2017 and December 28, 2016 , indefinite-lived intangible assets relating to transferable liquor licenses totaled $894 and $701 , respectively. We evaluate our indefinite-lived intangible assets for impairment annually during our fiscal fourth quarter, and whenever events or changes in circumstances indicate that an impairment may exist. When evaluating other intangible assets for impairment, we may first perform a qualitative assessment to determine whether it is more likely than not that an intangible asset group is impaired. If we do not perform the qualitative assessment, or if we determine that it is not more likely than not that the fair value of the intangible asset group exceeds its carrying amount, we calculate the estimated fair value of the intangible asset group. If the carrying amount of the intangible asset group exceeds the estimated fair value, an impairment charge is recorded to reduce the carrying value to the estimated fair value. In addition, we continuously monitor and may revise our intangible asset useful lives if and when facts and circumstances change.
Equity-based Compensation	Equity-based Compensation Equity-based compensation expense is measured based on fair value. For awards with graded-vesting features and service conditions only, compensation expense is recognized on a straight-line basis over the total requisite service period for the entire award. For awards with graded-vesting features and a combination of service and performance conditions, compensation expense is recognized using a graded-vesting attribution method over the vesting period based on the most probable outcome of the performance conditions. Forfeitures are recognized as they occur for all equity awards. Equity-based compensation expense is included within general and administrative expenses and labor and related expenses on the Consolidated Statements of Income (Loss) .
Leases	Leases We lease all of our domestic company-operated Shacks, our home office and certain equipment under various non-cancelable lease agreements that expire on various dates through 2035. Generally, our real estate leases have initial terms ranging from 10 to 15 years and typically include two five -year renewal options. At the inception of each lease, we determine its classification as an operating or capital lease. Most of our leases are classified as operating leases and typically provide for fixed minimum rent payments and/or contingent rent payments based upon sales in excess of specified thresholds. When the achievement of such sales thresholds are deemed to be probable, contingent rent is accrued in proportion to the sales recognized during the period. For operating leases that include rent holidays and rent escalation clauses, we recognize rent expense on a straight-line basis over the lease term from the date we take possession of the leased property. The difference between the straight-line rent amounts and amounts payable under the lease agreements is recorded as deferred rent and is included as rent expense in occupancy and related expenses on the Consolidated Statements of Income (Loss) . Rent expense incurred before a Shack opens is recorded in pre-opening costs. Once a domestic company-operated Shack opens, we record the straight-line rent expense and any contingent rent, if applicable, in occupancy and related expenses on the Consolidated Statements of Income (Loss) . Many of our leases also require us to pay real estate taxes, common area maintenance costs and other occupancy costs which are included in occupancy and related expenses on the Consolidated Statements of Income (Loss) . We expend cash for leasehold improvements to build out and equip our leased premises. Generally, a portion of the leasehold improvements and building costs are reimbursed by our landlords as landlord incentives pursuant to agreed-upon terms in our lease agreements. If obtained, landlord incentives usually take the form of up-front cash, full or partial credits against our future minimum or contingent rents otherwise payable by us, or a combination thereof. When contractually due, we classify landlord incentives as deferred rent on the Consolidated Balance Sheets and amortize the landlord incentives on a straight-line basis over the lease term as a reduction of occupancy costs and related expenses or pre-opening costs on the Consolidated Statements of Income (Loss) . Lease Financing Arrangements In certain leasing arrangements, due to our involvement in the construction of the leased assets, we are considered the owner of the leased assets for accounting purposes. In such cases, in addition to capitalizing our own construction costs, we capitalize the construction costs funded by the landlord related to our leased premises, and also recognize a corresponding liability for those costs as deemed landlord financing. If, upon completion of construction, the arrangement does not meet the sales recognition criteria under the sale-leaseback accounting guidance, we are precluded from de-recognizing the landlord-funded asset and related financing obligation and continue to account for the landlord-funded asset as if we were the legal owner. If de-recognition is permitted we are required to account for the lease as either an operating or capital lease. As of December 27, 2017 , we were deemed to be the accounting owner of 23 leased Shacks, 11 of which were under construction as of the end of the period.
Revenue Recognition	Revenue Recognition Revenue consists of Shack sales and licensing revenue. Revenue from Shack sales are presented net of discounts and recognized when food and beverage products are sold. Sales tax collected from customers is excluded from Shack sales and the obligation is included in sales tax payable until the taxes are remitted to the appropriate taxing authorities. Revenue from our gift cards are deferred and recognized upon redemption. Licensing revenues include initial territory fees, restaurant opening fees, and ongoing licensing fees from licensed Shacks. Initial territory fees are recorded as deferred revenue when received and recognized as revenue on a straight-line basis over the term of the licensing agreement. Restaurant opening fees are recorded as deferred revenue when received, and recognized as revenue when a licensed Shack is opened and all material services and conditions related to the fee have been substantially performed. Ongoing licensing fees from these Shacks are based on a percentage of sales and are recognized as revenue as the fees are earned and become receivable from the licensee.
Income Taxes	Income Taxes We account for income taxes pursuant to the asset and liability method which requires the recognition of deferred income tax assets and liabilities related to the expected future tax consequences arising from temporary differences between the carrying amounts and tax bases of assets and liabilities based on enacted statutory tax rates applicable to the periods in which the temporary differences are expected to reverse. Any effects of changes in income tax rates or laws are included in income tax expense in the period of enactment. A valuation allowance is recognized if we determine it is more likely than not that all or a portion of a deferred tax asset will not be recognized.
Pre-Opening Costs	Pre-Opening Costs Pre-opening costs are expensed as incurred and consist primarily of legal fees, marketing expenses, occupancy, manager and employee wages, travel and related training costs incurred prior to the opening of a Shack.
Advertising	Advertising The cost of advertising is expensed as incurred.
Recently Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements We adopted the Accounting Standards Updates (“ASUs”) summarized below in fiscal 2017. The effects of adoption did not have a material impact on our consolidated financial statements. Accounting Standards Update (“ASU”) Description Date Adopted Improvements to Employee Share-Based Payment Accounting (ASU 2016-09) This standard simplifies certain aspects of accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, certain classifications on the statement of cash flows, and an option to recognize gross stock compensation expense with actual forfeitures recognized as they occur. Upon adoption, we made such policy election. The adoption methodology applied varied based on each applicable provision of the standard, and none of the provisions had a material impact on our consolidated financial statements. December 29, 2016 Simplifying the Measurement of Inventory (ASU 2015-11) This standard applies to inventory measured using methods other than last-in, first-out (LIFO) or the retail method, and requires entities to measure such inventory at the lower of cost or net realizable value. It was applied prospectively. December 29, 2016 Recently Issued Accounting Pronouncements Accounting Standards Update (“ASU”) Description Expected Impact Effective Date Statement of Cash Flows: Classification of Certain Cash Receipts and Payments (ASU 2016-15) This standard provides guidance on eight specific cash flow issues with the objective of reducing diversity in practice. It should be applied retrospectively to each period presented, subject to certain conditions. We do not expect this standard to have a material impact on our consolidated financial statements. December 28, 2017 Recognition and Measurement of Financial Assets and Financial Liabilities (ASU 2016-01) For public business entities, this standard requires: (i) certain equity investments to be measured at fair value with changes in fair value recognized in net income; (ii) a qualitative assessment to identify impairment of equity investments without readily determinable fair values; (iii) elimination of the requirement to disclose the method(s) and significant assumptions used to estimate the fair value for financial instruments measured at amortized cost on the balance sheet; (iv) use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (v) separate presentation in other comprehensive income of the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value in accordance with the fair value option for financial instruments; (vi) separate presentation of financial assets and liabilities by measurement category and form of financial asset in the financial statements; and (vii) an entity to evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the entity’s other deferred tax assets. The standard should be applied by means of a cumulative-effect adjustment to the balance sheet at the beginning of the fiscal year of adoption. Early adoption is permitted, subject to certain conditions resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value. We do not expect this standard to have a material impact on our consolidated financial statements. December 28, 2017 Leases (ASU 2016-02, 2018-01) This standard establishes a new lease accounting model, which introduces the recognition of lease assets and liabilities for those leases classified as operating leases under previous GAAP. It should be applied using a modified retrospective approach, with the option to elect various practical expedients. Early adoption is permitted. We are currently evaluating the impact this standard will have on our consolidated financial statements. We have developed an implementation project plan, and are in process of identifying the complete population of leases to be analyzed under the new standard. We plan to adopt the standard on December 27, 2018. December 27, 2018 Accounting Standards Update (“ASU”) Description Expected Impact Effective Date Revenue from Contracts with Customers and related standards (ASU’s 2014-09, 2015-14, 2016-08, 2016-10, 2016-12, 2016-20) This standard supersedes the existing revenue recognition guidance and provides a new framework for recognizing revenue. The core principle of the standard is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. The new standard also requires significantly more comprehensive disclosures than the existing standard. Guidance subsequent to ASU 2014-09 has been issued to clarify various provisions in the standard, including principal versus agent considerations, identifying performance obligations, licensing transactions, as well as various technical corrections and improvements. This standard may be adopted using either a retrospective or modified retrospective method. Early adoption is permitted. We are substantially complete with our evaluation of the impact this standard is expected to have on our consolidated financial statements. Licensing revenue Revenue recognition related to sales-based royalties, which represents a significant portion of the licensing revenue balance, will not change from current policy. However, the pattern and timing of revenue recognition related to the fixed fees associated with our licensing agreements (such as restaurant opening and initial territory fees) will differ from current policy. Currently, restaurant opening fees are recorded as deferred revenue when received and proportionate amounts are recognized as revenue when a licensed Shack is opened and all material services and conditions related to the fee have been substantially performed. Territory fees are recorded as deferred revenue when received and recognized as revenue on a straight-line basis over the term of the license agreement, which generally begins upon execution of the contract. Under the new standard, the license granted to each restaurant under each existing contract is considered a performance obligation. All other promises (such as providing assistance during the opening of a restaurant) will be combined with the license as one performance obligation. Accordingly, we will allocate the total transaction price (comprised of the restaurant opening and territory fees) to each restaurant expected to be opened by the licensee under the contract. We will recognize the fee allocated to each restaurant as revenue on a straight-line basis over the restaurant’s license term, which generally begins when the restaurant opens. Shack sales We do not currently expect a significant impact to Shack sales as a result of the new revenue standard. Adoption and transition adjustment We plan to adopt the standard on December 28, 2017, utilizing a modified retrospective transition approach. The adoption will result in a decrease to retained earnings of approximately $1,574 on the transition date, with a corresponding increase of $1,769 in other long-term liabilities, a decrease of $68 in other current liabilities, an increase of $100 to accounts receivable, with the remaining impact representing the tax impact of the transition adjustment, as an increase to deferred tax assets. December 28, 2017

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 27, 2017
Fair Value Disclosures [Abstract]
Schedule of Cash and Cash Equivalents	The following tables summarize our cash, cash equivalents and marketable securities by significant investment categories as of December 27, 2017 and December 28, 2016 : December 27, 2017 Cost Basis Gross Unrealized Gains Gross Unrealized Losses Fair Value Cash and Cash Equivalents Marketable Securities Cash $ 16,138 $ — $ — $ 16,138 $ 16,138 $ — Level 1: Money market funds 5,369 — — 5,369 5,369 — Mutual funds 60,985 61 (122 ) 60,924 — 60,924 Level 2: Corporate debt securities (1) 2,125 2 (15 ) 2,112 — 2,112 Total $ 84,617 $ 63 $ (137 ) $ 84,543 $ 21,507 $ 63,036 December 28, 2016 Cost Basis Gross Unrealized Gains Gross Unrealized Losses Fair Value Cash and Cash Equivalents Marketable Securities Cash $ 6,322 $ — $ — $ 6,322 $ 6,322 $ — Level 1: Money market funds 5,285 — — 5,285 5,285 — Mutual funds 60,232 — — 60,232 — 60,232 Level 2: Corporate debt securities (1) 2,473 3 (30 ) 2,446 — 2,446 Total $ 74,312 $ 3 $ (30 ) $ 74,285 $ 11,607 $ 62,678 (1) Corporate debt securities were measured at fair value using a market approach utilizing observable prices for identical securities or securities with similar characteristics and inputs that are observable or can be corroborated by observable market data.
Schedule of Unrealized Loss on Investments	The following tables summarize the gross unrealized losses and fair values for those investments that were in an unrealized loss position as of December 27, 2017 and December 28, 2016 , aggregated by investment category and the length of time that individual securities have been in a continuous loss position: December 27, 2017 Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Money market funds $ — $ — $ — $ — $ — $ — Mutual funds — — — — — — Corporate debt securities 1,675 (12 ) 162 (3 ) 1,837 (15 ) Total $ 1,675 $ (12 ) $ 162 $ (3 ) $ 1,837 $ (15 ) December 28, 2016 Less than 12 Months 12 Months or Greater Total Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss Money market funds $ — $ — $ — $ — $ — $ — Mutual funds — — — — — — Corporate debt securities 1,244 (10 ) 540 (20 ) 1,784 (30 ) Total $ 1,244 $ (10 ) $ 540 $ (20 ) $ 1,784 $ (30 )
Schedule of Gain (Loss) on Investments	A summary of other income from available-for-sale securities recognized during fiscal 2017 , 2016 and 2015 is as follows: 2017 2016 2015 Available-for-sale securities: Dividend income $ 830 $ 296 $ — Interest income 77 88 7 Loss on investments (5 ) (7 ) — Total other income, net $ 902 $ 377 $ 7
Schedule of Realized Gain (Loss)	A summary of available-for-sale securities sold and gross realized gains and losses recognized during fiscal 2017 and 2016 is as follows: 2017 2016 Available-for-sale securities: Gross proceeds from sales and redemptions $ 2,223 $ 938 Cost basis of sales and redemptions 2,271 956 Gross realized gains included in net income 1 2 Gross realized losses included in net income (49 ) (20 ) Amounts reclassified out of accumulated other comprehensive loss 47 19
Schedule of Investments Classified by Contractual maturity Dates	The following table summarizes the estimated fair value of our investments in marketable debt securities, accounted for as available-for-sale securities and classified by the contractual maturity date of the securities: December 27 Due within one year $ 2,112 Due after one year through 5 years — Due after 5 years through 10 years — Due after 10 years — Total $ 2,112

ACCOUNTS RECEIVABLE (Tables)

ACCOUNTS RECEIVABLE (Tables)	12 Months Ended
	Dec. 27, 2017
Receivables [Abstract]
Schedule of Accounts Receivable	The components of accounts receivable as of December 27, 2017 and December 28, 2016 are as follows: December 27 December 28 Landlord receivables $ 1,660 $ 2,606 Licensing receivables 1,422 1,278 Credit card receivables 2,018 1,589 Other receivables 541 533 Accounts receivable $ 5,641 $ 6,006

INVENTORIES (Tables)

INVENTORIES (Tables)	12 Months Ended
	Dec. 27, 2017
Inventory Disclosure [Abstract]
Inventories	Inventories consisted of the following: December 27 December 28 Food $ 874 $ 543 Wine 69 47 Beer 85 58 Beverages 111 79 Retail merchandise 119 79 Inventories $ 1,258 $ 806

PROPERTY AND EQUIPMENT (Tables)

PROPERTY AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 27, 2017
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment	Property and equipment consisted of the following: December 27 December 28 Leasehold improvements $ 166,963 $ 120,629 Landlord funded assets 7,472 — Equipment 31,608 23,194 Furniture and fixtures 10,128 7,342 Computer equipment and software 12,721 8,710 Construction in progress (includes assets under construction from deemed landlord financing) 16,458 13,510 Property and equipment, gross 245,350 173,385 Less: accumulated depreciation (58,255 ) (37,121 ) Property and equipment, net $ 187,095 $ 136,264

SUPPLEMENTAL BALANCE SHEET IN36

SUPPLEMENTAL BALANCE SHEET INFORMATION (Tables)	12 Months Ended
	Dec. 27, 2017
Supplemental Balance Sheet Disclosures [Abstract]
Components of Other Current Liabilities	The components of other current liabilities as of December 27, 2017 and December 28, 2016 are as follows: December 27 December 28 Sales tax payable $ 1,813 $ 1,324 Current portion of liabilities under tax receivable agreement 937 4,580 Gift card liability 1,472 1,153 Other 3,715 3,116 Other current liabilities $ 7,937 $ 10,173

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 27, 2017
Leases [Abstract]
Schedule of Rent Expense	A summary of rent expense under operating lease agreements is as follows: 2017 2016 2015 Minimum rent $ 20,421 $ 15,408 $ 10,796 Deferred rent 838 2,122 1,482 Contingent rent 4,902 4,294 2,959 Total rent expense $ 26,161 $ 21,824 $ 15,237
Schedule of Future Minimum Rental Payments	As of December 27, 2017 , future minimum lease payments under non-cancelable operating leases and lease financing arrangements consisted of the following: Operating Leases Deemed Landlord Financing (1) 2018 $ 24,123 $ 3,679 2019 26,045 4,614 2020 25,817 4,695 2021 26,076 4,747 2022 26,506 4,816 Thereafter 143,244 27,438 Total minimum lease payments $ 271,811 $ 49,989 (1) Amounts include minimum lease payments for 11 leases under construction as of December 27, 2017 where we are deemed the accounting owner. Final classification of lease payments under deemed landlord financing is subject to change pending sale lease-back analysis performed at the store opening date.

NON-CONTROLLING INTERESTS (Tabl

NON-CONTROLLING INTERESTS (Tables)	12 Months Ended
	Dec. 27, 2017
Noncontrolling Interest [Abstract]
Schedule of Ownership Interest in SSE Holdings	The following table summarizes the ownership interest in SSE Holdings as of December 27, 2017 and December 28, 2016 : 2017 2016 LLC Interests Ownership % LLC Interests Ownership % Number of LLC Interests held by Shake Shack Inc. 26,527,477 72.1 % 25,151,384 69.1 % Number of LLC Interests held by non-controlling interest holders 10,250,007 27.9 % 11,253,592 30.9 % Total LLC Interests outstanding 36,777,484 100.0 % 36,404,976 100.0 %
Schedule of Non-Controlling Interest	The following table summarizes the effects of changes in ownership in SSE Holdings on our equity during fiscal 2017 , 2016 and 2015 . 2017 2016 2015 Net income (loss) attributable to Shake Shack Inc. $ (320 ) $ 12,446 $ (8,776 ) Other comprehensive loss: Unrealized holding losses on available-for-sale securities (34 ) (10 ) (5 ) Transfers (to) from non-controlling interests: Increase in additional paid-in capital as a result of settlement of unit appreciation rights — — 987 Decrease in additional paid-in capital as a result of the organizational transactions completed in connection with our IPO — — (75,182 ) Increase in additional paid-in capital as a result of the redemption of LLC Interests 4,415 16,986 19,934 Increase in additional paid-in capital as a result of the USC Merger — — 5,908 Increase in additional paid-in capital as a result of stock option exercises and the related income tax effect 4,451 825 — Total effect of changes in ownership interest on equity attributable to Shake Shack Inc. $ 8,512 $ 30,247 $ (57,134 )

EQUITY-BASED COMPENSATION (Tabl

EQUITY-BASED COMPENSATION (Tables)	12 Months Ended
	Dec. 27, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Equity-Based Compensation Expense Recognized	A summary of equity-based compensation expense recognized during fiscal 2017 , 2016 and 2015 is as follows: 2017 2016 2015 Unit appreciation rights $ — $ — $ 11,762 Restricted Class B units — — 605 Stock options 3,474 4,262 4,314 Performance stock units 1,869 1,092 — Restricted stock units 280 — — Equity-based compensation expense $ 5,623 $ 5,354 $ 16,681 Total income tax benefit recognized related to equity-based compensation $ 198 $ 168 $ 482
Schedule of Fair Value of Stock Options	The fair value of stock option awards was determined on the grant date using the Black-Scholes valuation model based on the following weighted-average assumptions: 2017 2016 2015 Expected term (years) (1) 7.5 5.5 7.5 Expected volatility (2) 44.5 % 50.7 % 35.1 % Risk-free interest rate (3) 2.1 % 1.5 % 1.6 % Dividend yield (4) — % — % — % (1) Expected term represents the estimated period of time until an award is exercised and was determined using the simplified method. (2) Expected volatility is based on the historical volatility of a selected peer group over a period equivalent to the expected term. (3) The risk-free rate rate is an interpolation of yields on U.S. Treasury securities with maturities equivalent to the expected term. (4) We have assumed a dividend yield of zero as we have no plans to declare dividends in the foreseeable future.
Schedule of Stock Options, Activity	A summary of stock option activity for fiscal years 2017 , 2016 and 2015 is as follows: Stock Options Weighted Average Exercise Price Aggregate Intrinsic Value Weighted Average Remaining Contractual Life (Years) Outstanding as of December 31, 2014 — $ — Granted 2,622,281 21.00 Exercised — — Forfeited (47,300 ) (21.00 ) Expired — — Outstanding as of December 30, 2015 2,574,981 $ 21.00 Granted 16,931 34.74 Exercised (160,230 ) 21.00 Forfeited (66,960 ) (21.00 ) Expired — — Outstanding as of December 28, 2016 2,364,722 $ 21.10 Granted 5,150 38.91 Exercised (359,011 ) 21.13 Forfeited (291,520 ) (21.00 ) Expired — — Outstanding as of December 27, 2017 1,719,341 $ 21.16 $ 39,851 7.1 Options vested and exercisable as of December 27, 2017 543,246 $ 21.34 $ 12,493 7.1 Options expected to vest as of December 27, 2017 1,098,577 $ 21.08 $ 25,549 7.1
Schedule of Nonvested Share Activity	A summary of unvested stock option activity for fiscal years 2017 , 2016 and 2015 is as follows: Stock Options Weighted Average Grant-Date Fair Value Unvested as of December 31, 2014 — $ — Vested — — Granted 2,622,281 8.53 Forfeited (47,300 ) 8.59 Unvested as of December 30, 2015 2,574,981 $ 8.53 Vested (562,296 ) 8.32 Granted 16,931 16.32 Forfeited (65,365 ) 8.59 Unvested as of December 28, 2016 1,964,251 $ 8.66 Vested (503,686 ) 8.85 Granted 5,150 19.42 Forfeited (289,620 ) 8.59 Unvested as of December 27, 2017 1,176,095 $ 8.64
Schedule of Information About Stock Options	The following table summarizes information about stock options outstanding and exercisable as December 27, 2017 : Options Outstanding Options Exercisable Number Outstanding at December 27, 2017 Weighted Average Remaining Contractual Life (Years) Weighted Average Exercise Price Number Exercisable at December 27, 2017 Weighted Average Remaining Contractual Life (Years) Weighted Average Exercise Price Exercise Price $21.00 1,700,665 7.1 $ 21.00 529,720 7.1 $ 21.00 $34.62 12,418 8.4 $ 34.62 12,418 8.4 $ 34.62 $36.41 1,108 8.9 $ 36.41 1,108 8.9 $ 36.41 $38.91 5,150 9.5 $ 38.91 — — $ —
Schedule of Stock Options Outstanding and Exercisable, Option Plans	A summary of performance stock unit activity for fiscal years 2017 and 2016 is as follows: Performance Stock Units Weighted Average Grant Date Fair Value Outstanding as of December 30, 2015 — $ — Granted 63,600 38.41 Performance achievement (1) — — Vested — — Forfeited (2,000 ) 38.43 Expired — — Outstanding as of December 28, 2016 61,600 $ 38.41 Granted 87,596 37.90 Performance achievement (1) 9,545 38.40 Vested (22,703 ) 38.40 Forfeited (11,196 ) 38.28 Expired — — Outstanding as of December 27, 2017 124,842 $ 38.06 (1) Represents incremental awards earned based on the achievement of performance conditions.

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 27, 2017
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	The components of income before income taxes are follows: 2017 2016 2015 Domestic $ 152,204 $ 20,623 $ 244 Foreign 8,089 7,873 6,184 Income before income taxes $ 160,293 $ 28,496 $ 6,428
Schedule of Components of Income Tax Expense	The components of income tax expense are as follows: 2017 2016 2015 Current income taxes: Federal $ 518 $ 3,767 $ 2,474 State and local 3,615 2,439 1,131 Foreign 942 667 433 Total current income taxes 5,075 6,873 4,038 Deferred income taxes: Federal 145,139 (48 ) (267 ) State and local 1,195 (475 ) (467 ) Total deferred income taxes 146,334 (523 ) (734 ) Income tax expense $ 151,409 $ 6,350 $ 3,304
Reconciliation of Income Tax Expense, US Income Tax Rate	Reconciliations of income tax expense computed at the U.S. federal statutory income tax rate to the recognized income tax expense and the U.S. statutory income tax rate to our effective tax rates are as follows: 2017 2016 2015 Expected U.S. federal income taxes at statutory rate $ 56,103 35.0 % $ 9,689 34.0 % $ 2,186 34.0 % State and local income taxes, net of federal benefit 2,590 1.6 % 1,461 5.1 % 663 10.3 % Foreign withholding taxes 942 0.6 % 667 2.3 % 433 6.7 % Non-deductible expenses 223 0.1 % 25 0.1 % 653 10.2 % Tax credits (1,230 ) (0.8 )% (779 ) (2.7 )% (141 ) (2.2 )% Non-controlling interest (3,273 ) (2.0 )% (3,765 ) (13.2 )% (490 ) (7.6 )% Remeasurement of deferred tax assets in connection with the enactment of the TCJA 138,636 86.5 % — — % — — % Remeasurement of deferred tax assets in connection with other tax rate changes 1,657 1.0 % (1,353 ) (4.7 )% — — % Remeasurement of liabilities under tax receivable agreement in connection with the enactment of the TCJA (44,051 ) (27.4 )% — — % — — % Other (188 ) (0.1 )% 405 1.4 % — — % Income tax expense $ 151,409 94.5 % $ 6,350 22.3 % $ 3,304 51.4 %
Schedule of Deferred Tax Assets and Liabilities	The components of deferred tax assets and liabilities are as follows: December 27 December 28 Deferred tax assets: Investment in partnership $ 137,449 $ 209,648 Tax Receivable Agreement 43,464 110,022 Deferred rent 571 561 Deferred revenue 59 53 Stock-based compensation 322 331 Net operating loss carryforwards 12,332 7,338 Tax credits 2,328 1,084 Other assets 176 108 Total gross deferred tax assets 196,701 329,145 Valuation allowance (10,114 ) (15,568 ) Total deferred tax assets, net of valuation allowance 186,587 313,577 Deferred tax liabilities: Property and equipment (673 ) (370 ) Total gross deferred tax liabilities (673 ) (370 ) Net deferred tax assets $ 185,914 $ 313,207

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	12 Months Ended
	Dec. 27, 2017
Earnings Per Share [Abstract]
Schedule of Earnings Per Share	The following table sets forth reconciliations of the numerators and denominators used to compute basic and diluted earnings per share of Class A common stock for fiscal 2017 , 2016 and 2015 . 2017 2016 2015 Numerator: Net income $ 8,884 $ 22,146 $ 3,124 Less: net income attributable to non-controlling interests 9,204 9,700 11,900 Net income (loss) attributable to Shake Shack Inc. $ (320 ) $ 12,446 $ (8,776 ) Denominator: Weighted-average shares of Class A common stock outstanding—basic 25,876 22,956 13,588 Effect of dilutive securities: Stock options — 493 — Weighted-average shares of Class A common stock outstanding—diluted 25,876 23,449 13,588 Earnings (loss) per share of Class A common stock—basic $ (0.01 ) $ 0.54 $ (0.65 ) Earnings (loss) per share of Class A common stock—diluted $ (0.01 ) $ 0.53 $ (0.65 )
Schedule of Antidilutive Securities	The following table presents potentially dilutive securities excluded from the computations of diluted earnings per share of Class A common stock for fiscal 2017 , 2016 and 2015 . 2017 2016 2015 Stock options (1) 1,719,341 (3) 125 (2) 2,574,981 (3) Performance stock units (1) 124,842 (3) 26,860 (4) — Restricted stock units (1) 44,476 (3) — — Shares of Class B common stock 10,250,007 (5) 11,253,592 (5) 16,460,741 (5) (1) Represents the number of instruments outstanding at the end of the period. Application of the treasury stock method would reduce this amount if they had a dilutive effect and were included in the computation of diluted earnings per share. (2) Excluded from the computation of diluted earnings per share of Class A common stock because the exercise price of the stock options exceeded the average market price of our Class A common stock during the period ("out-of-the-money"). (3) Excluded from the computation of diluted earnings per share of Class A common stock because the effect would have been anti-dilutive. (4) Weighted-average number of securities excluded from the computation of diluted earnings per share of Class A common stock because the performance conditions were not met for a portion of the fiscal year. (5) Shares of our Class B common stock are considered potentially dilutive shares of Class A common stock. Amounts have been excluded from the computations of diluted earnings per share of Class A common stock because the effect would have been anti-dilutive under the if-converted and two-class methods.

SUPPLEMENTAL CASH FLOW INFORM42

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)	12 Months Ended
	Dec. 27, 2017
Supplemental Cash Flow Elements [Abstract]
Schedule of Cash Flow Information	The following table sets forth supplemental cash flow information for fiscal 2017 , 2016 and 2015 : 2017 2016 2015 Cash paid for: Income taxes, net of refunds $ 2,261 $ 1,823 $ 416 Interest, net of amounts capitalized 1,106 54 92 Non-cash investing activities: Accrued purchases of property and equipment 7,526 6,150 4,904 Capitalized landlord assets for leases where we are deemed the accounting owner 10,125 1,985 — Capitalized equity-based compensation 109 139 — Class A common stock issued in connection with the acquisition of the former indirect members of SSE Holdings — — 6 Class A common stock issued in connection with the USC Merger — — 2 Non-cash financing activities: Cancellation of Class B common stock in connection with the Organizational Transactions — — (6 ) Class A common stock issued in connection with the redemption of LLC Interests 1 5 6 Cancellation of Class B common stock in connection with the redemption of LLC Interests (1 ) (5 ) (6 ) Cancellation of Class B common stock in connection with the USC Merger — — (2 ) Establishment of liabilities under tax receivable agreement 18,973 100,063 173,090 Accrued distributions payable to non-controlling interest holders — 607 —

GEOGRAPHIC INFORMATION (Tables)

GEOGRAPHIC INFORMATION (Tables)	12 Months Ended
	Dec. 27, 2017
Segment Reporting [Abstract]
Revenue from Customers by Geographic Areas	Revenue by geographic area for fiscal 2017 , 2016 and 2015 is as follows: 2017 2016 2015 United States $ 348,575 $ 260,602 $ 184,408 Other countries 10,235 7,873 6,184 Total revenue $ 358,810 $ 268,475 $ 190,592

SELECTED QUARTERLY FINANCIAL 44

SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Tables)	12 Months Ended
	Dec. 27, 2017
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	The following table sets forth certain unaudited financial information for each quarter of fiscal 2017 and 2016 . The unaudited quarterly information includes all adjustments (consisting of normal recurring adjustments) that, in the opinion of management, are necessary for the fair presentation of the information presented. Operating results for interim periods are not necessarily indicative of the results that may be expected for a full fiscal year. 2017 First Second Third Fourth Quarter Quarter Quarter Quarter Total revenue $ 76,749 $ 91,316 $ 94,609 $ 96,136 Operating income 5,628 11,737 10,610 5,838 Net income (loss) 3,862 8,184 7,870 (11,032 ) Net income (loss) attributable to Shake Shack Inc. 2,267 4,879 4,997 (12,463 ) Earnings (loss) per share (1) : Basic $ 0.09 $ 0.19 $ 0.19 $ (0.47 ) Diluted $ 0.09 $ 0.19 $ 0.19 $ (0.47 ) 2016 First Second Third Fourth Quarter Quarter Quarter Quarter Total revenue $ 54,165 $ 66,472 $ 74,567 $ 73,271 Operating income 4,714 8,933 9,170 4,988 Net income 3,351 6,549 6,789 5,457 Net income attributable to Shake Shack Inc. 1,462 3,298 3,766 3,920 Earnings per share (1) : Basic $ 0.07 $ 0.15 $ 0.16 $ 0.16 Diluted $ 0.07 $ 0.14 $ 0.15 $ 0.15 (1) Basic and diluted earnings per share are computed independently for each of the quarters presented. Therefore, the sum of quarterly basic and diluted earnings per share amounts may not equal annual basic and diluted earnings per share amounts.

NATURE OF OPERATIONS - Organiza

NATURE OF OPERATIONS - Organization and Nature of Operations - Franchiser (Details)	Dec. 27, 2017Restaurant
Franchisor Disclosure [Line Items]
Number of Restaurants	159
Company-operated | United States
Franchisor Disclosure [Line Items]
Number of Restaurants	90
Licensed | United States
Franchisor Disclosure [Line Items]
Number of Restaurants	10
Licensed | Other countries
Franchisor Disclosure [Line Items]
Number of Restaurants	59

NATURE OF OPERATIONS - Initial

NATURE OF OPERATIONS - Initial Public Offering (Details) - Common stock - Class A Common Stock - USD ($) $ / shares in Units, $ in Thousands	Feb. 04, 2015	Dec. 30, 2015
Class of Stock [Line Items]
Shares issued during the period (in shares)	5,968,841	5,750,000
IPO
Class of Stock [Line Items]
Shares issued during the period (in shares)	5,750,000
Shares issued, share price (in dollars per share)	$ 21
Proceeds of issuance of initial public offering net of underwriting discounts and commissions	$ 112,298
Over-allotment option
Class of Stock [Line Items]
Shares issued during the period (in shares)	750,000

NATURE OF OPERATIONS - Organi47

NATURE OF OPERATIONS - Organizational Transactions (Details)	Feb. 04, 2015shares	Feb. 04, 2015	Feb. 04, 2015entity	Feb. 04, 2015business	Feb. 28, 2015shares	Dec. 27, 2017shares	Dec. 28, 2016shares	Dec. 30, 2015shares
Class of Stock [Line Items]
Number of entities acquired			2	2
LLC interests acquired (in shares)	5,968,841				5,968,841	1,003,585	5,207,149
Ownership percent of noncontrolling interest	33.30%	33.30%	33.30%	33.30%		72.10%	69.10%
Noncontrolling owners ownership percentage	66.70%	66.70%	66.70%	66.70%		27.90%	30.90%
Class B Common Stock
Class of Stock [Line Items]
Ratio of common stock to limited liability company interest		1
Class B Common Stock | Common stock
Class of Stock [Line Items]
Shares issued during the period (in shares)	30,160,694
Effect of redemption (in shares)	5,968,841					1,003,585	5,207,149
Class A Common Stock
Class of Stock [Line Items]
Ratio of common stock to limited liability company interest		1
Class A Common Stock | Common stock
Class of Stock [Line Items]
Shares issued during the period (in shares)	5,968,841							5,750,000

NATURE OF OPERATIONS - Secondar

NATURE OF OPERATIONS - Secondary Offering (Details) - $ / shares	Feb. 04, 2015	Dec. 30, 2015	Aug. 31, 2015	Feb. 28, 2015	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Class of Stock [Line Items]
Number of units redeemed (in shares)				339,306			1,727,804
Units acquired during the period (in shares)	5,968,841			5,968,841	1,003,585	5,207,149
Ownership percent of noncontrolling interest	33.30%				72.10%	69.10%
Noncontrolling owners ownership percentage	66.70%				27.90%	30.90%
Class A Common Stock | Common stock
Class of Stock [Line Items]
Redemptions (in shares)					1,003,585	5,207,149
Shares issued during the period (in shares)	5,968,841						5,750,000
Class B Common Stock | Common stock
Class of Stock [Line Items]
Effect of redemption (in shares)	5,968,841				1,003,585	5,207,149
Shares issued during the period (in shares)	30,160,694
Secondary offering
Class of Stock [Line Items]
Units acquired during the period (in shares)			3,155,273
Secondary offering | Class A Common Stock | Common stock
Class of Stock [Line Items]
Total shares offered (in shares)			4,000,000
Shares issued, share price (in dollars per share)			$ 60
Conversion of units from former equity owners (in shares)			844,727
Redemptions (in shares)			3,155,273
Secondary offering | Class B Common Stock | Common stock
Class of Stock [Line Items]
Effect of redemption (in shares)			3,155,273
USC Merger
Class of Stock [Line Items]
Units acquired during the period (in shares)		1,727,804
USC Merger | Class A Common Stock | Common stock
Class of Stock [Line Items]
Redemptions (in shares)							1,727,804
Shares issued during the period (in shares)		1,727,804
USC Merger | Class B Common Stock | Common stock
Class of Stock [Line Items]
Redemptions (in shares)							1,727,804
Effect of redemption (in shares)		1,727,804
Limited Liability Company
Class of Stock [Line Items]
Number of units redeemed (in shares)					1,003,585	5,207,149
Limited Liability Company | Secondary offering
Class of Stock [Line Items]
Number of units redeemed (in shares)			3,155,273

SUMMARY OF SIGNIFICANT ACCOUN49

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Basis of Presentation (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Net assets of SSE Holdings	$ 197,301	$ 158,845

SUMMARY OF SIGNIFICANT ACCOUN50

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Segment Reporting (Details)	12 Months Ended
	Dec. 27, 2017operating_segmentreportable_segment
Accounting Policies [Abstract]
Number of operating segments | operating_segment	1
Number of reportable segments | reportable_segment	1

SUMMARY OF SIGNIFICANT ACCOUN51

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment (Details) - USD ($)	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Property, Plant and Equipment [Line Items]
Impairment charges	$ 0	$ 0	$ 0
Equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life of asset	3 years
Equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life of asset	7 years
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Useful life of asset	3 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Useful life of asset	7 years
Computer equipment and software | Minimum
Property, Plant and Equipment [Line Items]
Useful life of asset	3 years
Computer equipment and software | Maximum
Property, Plant and Equipment [Line Items]
Useful life of asset	7 years
Leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful life of asset	10 years
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful life of asset	15 years
Landlord funded assets | Minimum
Property, Plant and Equipment [Line Items]
Useful life of asset	10 years
Landlord funded assets | Maximum
Property, Plant and Equipment [Line Items]
Useful life of asset	15 years

SUMMARY OF SIGNIFICANT ACCOUN52

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Other Assets (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Accounting Policies [Abstract]
Indefinite-lived intangible assets	$ 894	$ 701

SUMMARY OF SIGNIFICANT ACCOUN53

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Leases (Details)	12 Months Ended
	Dec. 27, 2017renewal_optionlease	Dec. 28, 2016lease
Operating Leased Assets [Line Items]
Number of renewal options | renewal_option	2
Period of renewal term	5 years
Number of sale leaseback transactions, accounting owner	23	8
Number of sale leaseback transactions	11
Minimum
Operating Leased Assets [Line Items]
Terms of lease contract	10 years
Maximum
Operating Leased Assets [Line Items]
Terms of lease contract	15 years

SUMMARY OF SIGNIFICANT ACCOUN54

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Advertising (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Accounting Policies [Abstract]
Advertising and promotions	$ 357	$ 147	$ 149

SUMMARY OF SIGNIFICANT ACCOUN55

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - ASU Update (Details) - Subsequent Event $ in Thousands	Dec. 28, 2017USD ($)
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New accounting pronouncement	$ 1,574
Other Noncurrent Liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New accounting pronouncement	1,769
Current Liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New accounting pronouncement	68
Accounts Receivable
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New accounting pronouncement	$ 100

FAIR VALUE MEASUREMENTS - Cash,

FAIR VALUE MEASUREMENTS - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	$ 21,507	$ 11,607	$ 70,849	$ 2,677
Cash and cash equivalents fair value	21,507	11,607
Gross Unrealized Gains	63	3
Gross Unrealized Losses	(137)	(30)
Fair value of marketable securities	63,036	62,678
Total cost basis	84,617	74,312
Total fair value	84,543	74,285
Level 1: | Mutual Fund
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	60,985	60,232
Cash and cash equivalents fair value	60,924	60,232
Gross Unrealized Gains	61
Gross Unrealized Losses	(122)
Fair value of marketable securities	60,924	60,232
Level 2: | Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Marketable securities cost Basis	2,125	2,473
Gross Unrealized Gains	2	3
Gross Unrealized Losses	(15)	(30)
Fair value of marketable securities	2,112	2,446
Cash
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	16,138	6,322
Cash and cash equivalents fair value	16,138	6,322
Money market funds | Level 1:
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	5,369	5,285
Cash and cash equivalents fair value	$ 5,369	$ 5,285

FAIR VALUE MEASUREMENTS - Addit

FAIR VALUE MEASUREMENTS - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Fair Value Disclosures [Abstract]
Net unrealized losses on available-for-sale securities	$ (74,000)	$ (27,000)
Impairment charges	$ 0	$ 0	$ 0

FAIR VALUE MEASUREMENTS - Sched

FAIR VALUE MEASUREMENTS - Schedule of Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value (less than 12 months)	$ 1,675	$ 1,244
Unrealized Loss (less than 12 months)	(12)	(10)
Fair Value (12 months or greater)	162	540
Unrealized Loss (12 months or greater)	(3)	(20)
Fair Value	1,837	1,784
Unrealized Loss	(15)	(30)
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value (less than 12 months)	1,675	1,244
Unrealized Loss (less than 12 months)	(12)	(10)
Fair Value (12 months or greater)	162	540
Unrealized Loss (12 months or greater)	(3)	(20)
Fair Value	1,837	1,784
Unrealized Loss	$ (15)	$ (30)

FAIR VALUE MEASUREMENTS - Sch59

FAIR VALUE MEASUREMENTS - Schedule of Income for AFS Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Fair Value Disclosures [Abstract]
Dividend income	$ 830	$ 296	$ 0
Interest income	77	88	7
Loss on investments	(5)	(7)	0
Total other income, net	$ 902	$ 377	$ 7

FAIR VALUE MEASUREMENTS - Sch60

FAIR VALUE MEASUREMENTS - Schedule of AFS Sold (Details) - USD ($)		12 Months Ended
		Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Available-for-sale securities:
Gross proceeds from sales and redemptions		$ 2,223,000	$ 938,000	$ 0
Cost basis of sales and redemptions		2,271,000	956,000
Gross realized gains included in net income		1,000	2,000
Gross realized losses included in net income		(49,000)	(20,000)
Amounts reclassified out of accumulated other comprehensive loss	[1]	$ 47,000	$ 19,000	$ 0
[1]	Net of tax benefit of $0 for fiscal years ended December 27, 2017, December 28, 2016 and December 30, 2015.

FAIR VALUE MEASUREMENTS - Esti

FAIR VALUE MEASUREMENTS - Estimated Fair Value of Investments (Details) $ in Thousands	Dec. 27, 2017USD ($)
Fair Value Disclosures [Abstract]
Due within one year	$ 2,112
Due after one year through 5 years	0
Due after 5 years through 10 years	0
Due after 10 years	0
Total	$ 2,112

ACCOUNTS RECEIVABLE - Schedule

ACCOUNTS RECEIVABLE - Schedule of Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Receivables [Abstract]
Landlord receivables	$ 1,660	$ 2,606
Licensing receivables	1,422	1,278
Credit card receivables	2,018	1,589
Other receivables	541	533
Accounts receivable	$ 5,641	$ 6,006

ACCOUNTS RECEIVABLE - Addition

ACCOUNTS RECEIVABLE - Additional Information (Details) - USD ($)	Dec. 27, 2017	Dec. 28, 2016
Receivables [Abstract]
Allowance for doubtful accounts	$ 0	$ 0

INVENTORIES - Schedule of Inven

INVENTORIES - Schedule of Inventories (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Inventory [Line Items]
Inventories	$ 1,258	$ 806
Food
Inventory [Line Items]
Inventories	874	543
Wine
Inventory [Line Items]
Inventories	69	47
Beer
Inventory [Line Items]
Inventories	85	58
Beverages
Inventory [Line Items]
Inventories	111	79
Retail merchandise
Inventory [Line Items]
Inventories	$ 119	$ 79

PROPERTY AND EQUIPMENT (Details

PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 245,350	$ 173,385
Less: accumulated depreciation	(58,255)	(37,121)
Property and equipment, net	187,095	136,264
Depreciation	21,704	14,502	$ 10,222
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	166,963	120,629
Landlord funded assets
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,472	0
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	31,608	23,194
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	10,128	7,342
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	12,721	8,710
Construction in progress (includes assets under construction from deemed landlord financing)
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 16,458	$ 13,510

SUPPLEMENTAL BALANCE SHEET IN66

SUPPLEMENTAL BALANCE SHEET INFORMATION (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Supplemental Balance Sheet Disclosures [Abstract]
Sales tax payable	$ 1,813	$ 1,324
Current portion of liabilities under tax receivable agreement	937	4,580
Gift card liability	1,472	1,153
Other	3,715	3,116
Other current liabilities	$ 7,937	$ 10,173

DEBT (Details)

DEBT (Details) - USD ($)	Feb. 04, 2015	May 31, 2016	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015	Mar. 31, 2013
Debt Instrument [Line Items]
Deemed landlord financing			$ 14,518,000	$ 2,007,000
Interest costs incurred			1,806,000	374,000	$ 440,000
Interest costs capitalized			164,000	0	$ 108,000
Notes payable
Debt Instrument [Line Items]
Notes payable face amount						$ 313,000
Stated interest rate						5.00%
Notes payable			$ 0	0
Letter of credit
Debt Instrument [Line Items]
Term to maturity			1 year
Revolving Credit Facility | Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 50,000,000
Current borrowing capacity	$ 20,000,000
Term to maturity	5 years
Short-term borrowings			$ 0	$ 0
Remaining borrowing capacity			19,317,000
Revolving Credit Facility | Letter of credit | Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 10,000,000
Current borrowing capacity			$ 683,000
Revolving Credit Facility | Minimum | Line of credit | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate		2.30%
Revolving Credit Facility | Minimum | Line of credit | Prime rate
Debt Instrument [Line Items]
Basis spread on variable rate		0.00%
Revolving Credit Facility | Maximum | Line of credit | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate		3.30%
Revolving Credit Facility | Maximum | Line of credit | Prime rate
Debt Instrument [Line Items]
Basis spread on variable rate		0.80%

LEASES - Summary of Rent Expens

LEASES - Summary of Rent Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Leases [Abstract]
Minimum rent	$ 20,421	$ 15,408	$ 10,796
Deferred rent	838	2,122	1,482
Contingent rent	4,902	4,294	2,959
Total rent expense	$ 26,161	$ 21,824	$ 15,237

LEASES - Narrative (Details)

LEASES - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 27, 2017USD ($)lease	Dec. 28, 2016USD ($)lease	Dec. 30, 2015USD ($)
Leases [Abstract]
Number of sale leaseback transactions, accounting owner | lease	23	8
Common area maintenance costs, real estate taxes, and other occocupancy costs not included in rent expense | $	$ 4,570	$ 3,229	$ 2,119
Number of sale leaseback transactions | lease	11
Deemed landlord financing | $	$ 14,518	$ 2,007

LEASES - Schedule of Future Min

LEASES - Schedule of Future Minimum Lease Payments (Details) $ in Thousands	12 Months Ended
	Dec. 27, 2017USD ($)lease
Operating Leases
2,018	$ 24,123
2,019	26,045
2,020	25,817
2,021	26,076
2,022	26,506
Thereafter	143,244
Total minimum lease payments	271,811
Deemed Landlord Financing
2,018	3,679
2,019	4,614
2,020	4,695
2,021	4,747
2,022	4,816
Thereafter	27,438
Total minimum lease payments	$ 49,989
Number of sale leaseback transactions | lease	11

EMPLOYEE BENEFIT PLANS - Deferr

EMPLOYEE BENEFIT PLANS - Deferred Compensation (Details) - Executive - Deferred Bonus - USD ($)	1 Months Ended	12 Months Ended
	Oct. 31, 2015	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015	Dec. 25, 2013
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation award due to executive					$ 2,450,000
Deferred compensation expense		$ 0	$ 0	$ 0	$ 2,054,000
Contributions by employer	$ 2,450,000

EMPLOYEE BENEFIT PLANS - Define

EMPLOYEE BENEFIT PLANS - Defined Contribution Plan (Details) - USD ($)	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 389,000	$ 257,000	$ 238,000
Defined Contribution Plan, Initial Contribution
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percentage	100.00%
Employer matching contribution as a percent of employees' gross pay	3.00%
Defined Contribution Plan, Additional Contribution
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percentage	50.00%
Employer matching contribution as a percent of employees' gross pay	3.00%
Defined Contribution Plan, Additional Contribution | Maximum
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution as a percent of employees' gross pay	5.00%

STOCKHOLDER'S EQUITY (Details)

STOCKHOLDER'S EQUITY (Details) $ / shares in Units, $ in Thousands	Feb. 04, 2015$ / sharesshares	Feb. 04, 2015$ / sharesshares	Feb. 04, 2015$ / sharesshares	Feb. 04, 2015entity$ / sharesshares	Feb. 04, 2015USD ($)$ / sharesshares	Feb. 04, 2015business$ / sharesshares	Feb. 04, 2015Vote / shares$ / sharesshares	Feb. 04, 2015board_of_director_class$ / sharesshares	Dec. 15, 2014	Dec. 30, 2015shares	Aug. 31, 2015$ / sharesshares	Feb. 28, 2015shares	Dec. 27, 2017USD ($)$ / sharesshares	Dec. 28, 2016USD ($)$ / sharesshares	Dec. 30, 2015USD ($)shares	Dec. 26, 2012shares
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000	10,000,000	10,000,000	10,000,000	10,000,000	10,000,000	10,000,000					10,000,000	10,000,000
Number of classes of directors | board_of_director_class								3
Board of directors, term	3 years
Number of votes per share | Vote / shares							1
Number of units redeemed (in shares)												339,306			1,727,804
Number of entities acquired				2		2
LLC interests acquired (in shares)		5,968,841										5,968,841	1,003,585	5,207,149
Member distribution threshold, percentage									27.30%
Member distributions | $					$ 11,125								$ 0	$ 0	$ 11,125
Class A Common Stock
Class of Stock [Line Items]
Common stock, shares, issued (in shares)													26,527,477	25,151,384
Common stock, shares authorized (in shares)	200,000,000	200,000,000	200,000,000	200,000,000	200,000,000	200,000,000	200,000,000	200,000,000					200,000,000	200,000,000
Common stock par value (in dollars per share) | $ / shares	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001					$ 0.001	$ 0.001
Ratio of common stock to limited liability company interest			1
Class B Common Stock
Class of Stock [Line Items]
Common stock, shares, issued (in shares)													10,250,007	11,253,592
Common stock, shares authorized (in shares)	35,000,000	35,000,000	35,000,000	35,000,000	35,000,000	35,000,000	35,000,000	35,000,000					35,000,000	35,000,000
Common stock par value (in dollars per share) | $ / shares	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001					$ 0.001	$ 0.001
Ratio of common stock to limited liability company interest			1
Secondary offering
Class of Stock [Line Items]
LLC interests acquired (in shares)											3,155,273
USC Merger
Class of Stock [Line Items]
LLC interests acquired (in shares)										1,727,804
Common stock | Class A Common Stock
Class of Stock [Line Items]
Shares issued during the period (in shares)		5,968,841													5,750,000
Redemptions (in shares)													1,003,585	5,207,149
Common stock | Class B Common Stock
Class of Stock [Line Items]
Shares issued during the period (in shares)		30,160,694
Effect of redemption (in shares)		5,968,841											1,003,585	5,207,149
Common stock | IPO | Class A Common Stock
Class of Stock [Line Items]
Shares issued during the period (in shares)		5,750,000
Shares issued, share price (in dollars per share) | $ / shares	$ 21	$ 21	$ 21	$ 21	$ 21	$ 21	$ 21	$ 21
Proceeds of issuance of initial public offering net of underwriting discounts and commissions | $					$ 112,298
Common stock | Over-allotment option | Class A Common Stock
Class of Stock [Line Items]
Shares issued during the period (in shares)		750,000
Common stock | Secondary offering | Class A Common Stock
Class of Stock [Line Items]
Shares issued, share price (in dollars per share) | $ / shares											$ 60
Total conversion of units (in shares)											4,000,000
Conversion of units from former equity owners (in shares)											844,727
Redemptions (in shares)											3,155,273
Common stock | Secondary offering | Class B Common Stock
Class of Stock [Line Items]
Effect of redemption (in shares)											3,155,273
Common stock | USC Merger | Class A Common Stock
Class of Stock [Line Items]
Shares issued during the period (in shares)										1,727,804
Redemptions (in shares)															1,727,804
Common stock | USC Merger | Class B Common Stock
Class of Stock [Line Items]
Redemptions (in shares)															1,727,804
Effect of redemption (in shares)										1,727,804
Limited Liability Company
Class of Stock [Line Items]
Number of units redeemed (in shares)													1,003,585	5,207,149
Limited Liability Company | Secondary offering
Class of Stock [Line Items]
Number of units redeemed (in shares)											3,155,273
Stock options
Class of Stock [Line Items]
LLC interests acquired (in shares)													372,508	154,976
Unit Appreciation Rights Plan | Unit appreciation rights
Class of Stock [Line Items]
Common stock, shares, issued (in shares)																339,306

NON-CONTROLLING INTERESTS - Nar

NON-CONTROLLING INTERESTS - Narrative (Details)	Feb. 04, 2015shares	Feb. 04, 2015	Feb. 04, 2015entity	Feb. 04, 2015business	Feb. 28, 2015shares	Dec. 27, 2017shares	Dec. 28, 2016shares	Dec. 30, 2015shares
Noncontrolling Interest [Line Items]
Weighted average ownership percentage						29.40%	36.80%
Units purchased during the period (shares)					5,750,000
Units acquired during the period (in shares)	5,968,841				5,968,841	1,003,585	5,207,149
Number of entities acquired			2	2
Number of units redeemed (in shares)					339,306			1,727,804
LLC interests issued for share-based compensation (shares)					339,306
Ownership percent of noncontrolling interest	33.30%	33.30%	33.30%	33.30%		72.10%	69.10%
Class A Common Stock
Noncontrolling Interest [Line Items]
Ratio of common stock to limited liability company interest		1
Limited Liability Company
Noncontrolling Interest [Line Items]
Number of units redeemed (in shares)						1,003,585	5,207,149
Stock options
Noncontrolling Interest [Line Items]
Units acquired during the period (in shares)						372,508	154,976

NON-CONTROLLING INTERESTS - Own

NON-CONTROLLING INTERESTS - Ownership Interest in SSE Holdings (Details) - shares	Dec. 27, 2017	Dec. 28, 2016	Feb. 04, 2015
Noncontrolling Interest [Abstract]
Number of LLC Interests held by Shake Shack Inc. (in shares)	26,527,477	25,151,384
Number of LLC Interests held by Shake Shack Inc. (in percentage)	72.10%	69.10%	33.30%
Number of LLC Interests held by non-controlling interest holders (in shares)	10,250,007	11,253,592
Number of LLC Interests held by non-controlling interest holders (in percentage)	27.90%	30.90%	66.70%
Total LLC Interests outstanding (in shares)	36,777,484	36,404,976
Total LLC Interests outstanding (in percentage)	100.00%	100.00%

NON-CONTROLLING INTERESTS - Sch

NON-CONTROLLING INTERESTS - Schedule of Non-Controlling Interest (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 27, 2017	Sep. 27, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 28, 2016	Sep. 28, 2016	Jun. 29, 2016	Mar. 30, 2016	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Noncontrolling Interest [Line Items]
Net income (loss) attributable to Shake Shack Inc.	$ (12,463)	$ 4,997	$ 4,879	$ 2,267	$ 3,920	$ 3,766	$ 3,298	$ 1,462	$ (320)	$ 12,446	$ (8,776)
Other comprehensive loss:
Unrealized holding losses on available-for-sale securities									(47)	(16)	(11)
Total effect of changes in ownership interest on equity attributable to Shake Shack Inc.									8,512	30,247	(57,134)
Unrealized holding losses on available-for-sale securities
Other comprehensive loss:
Unrealized holding losses on available-for-sale securities									(34)	(10)	(5)
Increase in additional paid-in capital as a result of settlement of unit appreciation rights
Other comprehensive loss:
Transfers (to) from non-controlling interests									0	0	987
Stock options
Other comprehensive loss:
Transfers (to) from non-controlling interests									4,451	825
Decrease in additional paid-in capital as a result of the organizational transactions completed in connection with our IPO
Other comprehensive loss:
Transfers (to) from non-controlling interests									0	0	(75,182)
Increase in additional paid-in capital as a result of the redemption of LLC Interests
Other comprehensive loss:
Transfers (to) from non-controlling interests									4,415	16,986	19,934
Increase in additional paid-in capital as a result of the USC Merger
Other comprehensive loss:
Transfers (to) from non-controlling interests									$ 0	$ 0	$ 5,908

EQUITY-BASED COMPENSATION - Sch

EQUITY-BASED COMPENSATION - Schedule of compensation expense recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	$ 5,623	$ 5,354	$ 16,681
Total income tax benefit recognized related to equity-based compensation	198	168	482
Unit appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	0	0	11,762
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	280	0	0
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	3,474	4,262	4,314
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	1,869	1,092	0
Class B Common Stock | Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense	$ 0	$ 0	$ 605

EQUITY-BASED COMPENSATION - Nar

EQUITY-BASED COMPENSATION - Narrative (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2015	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015	Dec. 26, 2012	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity based compensation		$ 109,000	$ 139,000	$ 0
Equity-based compensation expense		5,623,000	5,354,000	16,681,000
Proceeds from stock option exercises		7,585,000	3,194,000	0
Issuance of common stock in settlement of unit appreciation rights				0
Unit appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense		0	0	11,762,000
Restricted Class B units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense		280,000	$ 0	0
Stock options outstanding (in shares)			0
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense		3,474,000	$ 4,262,000	4,314,000
Fair value vested		4,458,000	4,678,000	0
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense		$ 1,869,000	$ 1,092,000	0
Minimum | Restricted Class B units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Maximum | Restricted Class B units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		5 years
2015 Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	5,865,522
2015 Incentive Award Plan | Minimum | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
2015 Incentive Award Plan | Maximum | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	5 years
Unit Appreciation Rights Plan | Unit appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)					31,303
Common stock, shares, issued (in shares)					339,306
Shares paid for tax withholding (in shares)					22,554
Equity-based compensation expense				$ 11,762,000
Stock options outstanding (in shares)		0	0
2015 Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)		1,719,341	2,364,722	2,574,981		0
Unrecognized compensation expense		$ 7,098,000
Weighted-average period for recognition compensation expense		2 years 1 month 5 days
Intrinsic value of stock options exercised		$ 12,493,000
Stock option exercises (in shares)		359,011	160,230	0
Proceeds from stock option exercises		$ 7,585,000
2015 Incentive Award Plan | Restricted Class B units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance shares granted (in shares)		44,476
Granted (in shares)		44,476	0	0
Granted (in USD per share)		$ 38.98
2015 Incentive Award Plan | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of stock options exercised		$ 8,333,000	$ 2,536,000
Vested (in shares)		(503,686)	(562,296)	0
2015 Incentive Award Plan | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Weighted-average period for recognition compensation expense		1 year 6 months 21 days
Performance period		1 year
Performance shares granted (in shares)		124,842	61,600	0
Shares expected to be recognized		$ 2,385,000
Granted (in shares)		87,596	63,600
Granted (in USD per share)		$ 37.90	$ 38.41
Issuance of common stock in settlement of unit appreciation rights		$ 1,453,000
Weighted average period		2 years 6 months 6 days
2015 Incentive Award Plan | Minimum | Restricted Class B units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		1 year
2015 Incentive Award Plan | Minimum | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of awards		0.00%
2015 Incentive Award Plan | Maximum | Restricted Class B units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		5 years
2015 Incentive Award Plan | Maximum | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of awards		125.00%

EQUITY-BASED COMPENSATION - S79

EQUITY-BASED COMPENSATION - Schedule of Fair Value of Stock Options (Details) - 2015 Incentive Award Plan - Stock options	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	7 years 6 months	5 years 6 months	7 years 6 months
Expected volatility	44.50%	50.70%	35.10%
Risk-free interest rate	2.10%	1.50%	1.60%
Dividend yield	0.00%	0.00%	0.00%

EQUITY-BASED COMPENSATION - S80

EQUITY-BASED COMPENSATION - Schedule of Stock Options (Details) - 2015 Incentive Award Plan - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Stock Options
Outstanding at beginning of period (in shares)	2,364,722	2,574,981	0
Granted (in shares)	5,150	16,931	2,622,281
Exercised (in shares)	(359,011)	(160,230)	0
Forfeited (in shares)	(291,520)	(66,960)	(47,300)
Expired (in shares)	0	0	0
Outstanding at end of period (in shares)	1,719,341	2,364,722	2,574,981
Options vested and exercisable at end of period (in shares)	543,246
Options expected to vest (in shares)	1,098,577
Weighted Average Exercise Price
Outstanding at beginning of period (in USD per share)	$ 21.10	$ 21	$ 0
Granted (in USD per share)	38.91	34.74	21
Exercised (in USD per share)	21.13	21	0
Forfeited (in USD per share)	(21)	(21)	(21)
Expired (in USD per share)	0	0	0
Outstanding at end of period (in USD per share)	21.16	$ 21.10	$ 21
Weighted average options vested and exercisable (in USD per share)	21.34
Options expected to vest (in USD per share)	$ 21.08
Aggregate Intrinsic Value
Outstanding at end of period	$ 39,851
Options exercised during period	12,493
Options expected to vest as of December 27, 2017	$ 25,549
Weighted Average Remaining Contractual Life (Years)
Outstanding at end of period	7 years 1 month 7 days
Options exercisable at end of year	7 years 1 month 5 days
Options expected to vest at end of year	7 years 1 month 12 days
Stock options
Stock Options
Nonvested beginning balance (in shares)	1,964,251	2,574,981	0
Granted (in shares)	5,150	16,931	2,622,281
Vested (in shares)	(503,686)	(562,296)	0
Forfeited (in shares)	(289,620)	(65,365)	(47,300)
Nonvested ending balance (in shares)	1,176,095	1,964,251	2,574,981
Weighted Average Exercise Price
Nonvested, beginning balance (in USD per share)	$ 8.66	$ 8.53	$ 0
Granted (in USD per share)	19.42	16.32	8.53
Vested (in USD per share)	8.85	8.32	0
Forfeited (in USD per share)	8.59	8.59	8.59
Nonvested, ending balance (in USD per share)	$ 8.64	$ 8.66	$ 8.53
Aggregate Intrinsic Value
Options exercised during period	$ 8,333	$ 2,536

EQUITY-BASED COMPENSATION - Sto

EQUITY-BASED COMPENSATION - Stock Options Outstanding and Exercisable (Details) - 2015 Incentive Award Plan	12 Months Ended
	Dec. 27, 2017$ / sharesshares
Twenty-One Dollars
Options Outstanding
Number Outstanding (in shares) | shares	1,700,665
Weighted Average Remaining Contractual Life (Years)	7 years 1 month 2 days
Weighted Average Exercise Price (in USD per share) | $ / shares	$ 21
Options Exercisable
Number Exercisable (in shares) | shares	529,720
Weighted Average Remaining Contractual Life (Years)	7 years 1 month 2 days
Weighted Average Exercise Price (in USD per share) | $ / shares	$ 21
Thirty-Four Point Sixty Two Dollars
Options Outstanding
Number Outstanding (in shares) | shares	12,418
Weighted Average Remaining Contractual Life (Years)	8 years 4 months 22 days
Weighted Average Exercise Price (in USD per share) | $ / shares	$ 34.62
Options Exercisable
Number Exercisable (in shares) | shares	12,418
Weighted Average Remaining Contractual Life (Years)	8 years 4 months 22 days
Weighted Average Exercise Price (in USD per share) | $ / shares	$ 34.62
Thirty-Six Point Forty One Dollars
Options Outstanding
Number Outstanding (in shares) | shares	1,108
Weighted Average Remaining Contractual Life (Years)	8 years 10 months 20 days
Weighted Average Exercise Price (in USD per share) | $ / shares	$ 36.41
Options Exercisable
Number Exercisable (in shares) | shares	1,108
Weighted Average Remaining Contractual Life (Years)	8 years 10 months 20 days
Weighted Average Exercise Price (in USD per share) | $ / shares	$ 36.41
Thirty-Eight Point Ninety One Dollars
Options Outstanding
Number Outstanding (in shares) | shares	5,150
Weighted Average Remaining Contractual Life (Years)	9 years 5 months 15 days
Weighted Average Exercise Price (in USD per share) | $ / shares	$ 38.91
Options Exercisable
Number Exercisable (in shares) | shares	0
Weighted Average Exercise Price (in USD per share) | $ / shares	$ 0

EQUITY-BASED COMPENSATION - Sum

EQUITY-BASED COMPENSATION - Summary of Performance Stock Activity (Details) - 2015 Incentive Award Plan - Performance Shares - $ / shares	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding at beginning of period (in shares)	61,600	0
Granted (in shares)	87,596	63,600
Performance achievement (in shares)	9,545	0
Vested (in shares)	(22,703)	0
Forfeited (in shares)	(11,196)	(2,000)
Expired (in shares)	0	0
Outstanding at end of period (in shares)	124,842	61,600
Stock Options
Outstanding at beginning of period (in USD per share)	$ 38.41	$ 0
Granted (in USD per share)	37.90	38.41
Performance achievement (in USD per share)	38.40	0
Vested (in USD per share)	38.40	0
Forfeited (in USD per share)	38.28	38.43
Expired (in USD per share)	0	0
Outstanding at end of period (in USD per share)	$ 38.06	$ 38.41

INCOME TAXES - Narrative (Detai

INCOME TAXES - Narrative (Details) - USD ($)	Feb. 04, 2015	Dec. 27, 2017	Feb. 28, 2015	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Income Tax Contingency [Line Items]
Income tax expense related to tax cuts and jobs act		$ 138,636,000
Effective income tax rate (percent)				94.50%	22.30%	51.40%
Deferred tax assets, carryforwards, federal		51,668,000		$ 51,668,000
Deferred tax assets, carryforwards, state and local		19,166,000		$ 19,166,000
Number of LLC interests (shares)				1,376,093
Additional deferred tax asset recognized, investment in partnership				$ 14,370,000
Reduction in basis due to amortization of deferred tax asset related to the investment in partnership [Line Items]				14,339,000
Valuation allowance		(10,114,000)		(10,114,000)	$ (15,568,000)
Additional deferred tax asset recognized, tax receivable agreement				7,661,000
Increase in valuation allowance				5,454,000
Uncertain tax positions		$ 0		$ 0	0
Percentage of tax benefits due to equity owners		85.00%		85.00%
Remaining percentage of tax benefits due to equity owners		15.00%		15.00%
Other income recognized related to reduction of tax receivable agreement liability				$ 4,844,000	$ 0	$ 0
LLC interests acquired (in shares)	5,968,841		5,968,841	1,003,585	5,207,149
Establishment of liabilities under tax receivable agreement				$ 18,973,000	$ 100,063,000	$ 173,090,000
Establishment of liabilities under tax receivable agreement		$ 159,373,000		159,373,000
Current portion of liabilities under tax receivable agreement		$ 937,000		937,000	$ 4,580,000
Members' Equity
Income Tax Contingency [Line Items]
Other income recognized related to reduction of tax receivable agreement liability				4,910,000
Other Income | Members' Equity
Income Tax Contingency [Line Items]
Other income recognized related to reduction of tax receivable agreement liability				$ 125,859,000

INCOME TAXES - Schedule of Com

INCOME TAXES - Schedule of Components of Income before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Income Tax Disclosure [Abstract]
Domestic	$ 152,204	$ 20,623	$ 244
Foreign	8,089	7,873	6,184
Income before income taxes	$ 160,293	$ 28,496	$ 6,428

INCOME TAXES - Schedule of Comp

INCOME TAXES - Schedule of Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Current income taxes:
Federal	$ 518	$ 3,767	$ 2,474
State and local	3,615	2,439	1,131
Foreign	942	667	433
Total current income taxes	5,075	6,873	4,038
Deferred income taxes:
Federal	145,139	(48)	(267)
State and local	1,195	(475)	(467)
Total deferred income taxes	146,334	(523)	(734)
Income tax expense	$ 151,409	$ 6,350	$ 3,304

INCOME TAXES - Reconciliation o

INCOME TAXES - Reconciliation of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Income Tax Disclosure [Abstract]
Income taxes at U.S. federal statutory rate	$ 56,103	$ 9,689	$ 2,186
U.S. federal statutory income tax rate, percentage	35.00%	34.00%	34.00%
State and local income taxes, net of federal benefit	$ 2,590	$ 1,461	$ 663
State and local income taxes, net of federal benefit, percentage	1.60%	5.10%	10.30%
Foreign withholding taxes	$ 942	$ 667	$ 433
Foreign withholding taxes, percentage	0.60%	2.30%	6.70%
Non-deductible expenses	$ 223	$ 25	$ 653
Non-deductible expenses, percentage	0.10%	0.10%	10.20%
Tax credits	$ (1,230)	$ (779)	$ (141)
Tax credits, percentage	(0.80%)	(2.70%)	(2.20%)
Non-controlling interest	$ (3,273)	$ (3,765)	$ (490)
Non-controlling interest, percentage	(2.00%)	(13.20%)	(7.60%)
Remeasurement of deferred tax assets in connection with the enactment of the TCJA	$ 138,636	$ 0	$ 0
Remeasurement of deferred tax assets in connection with the enactment of the TCJA, percentage	86.50%	0.00%	0.00%
Remeasurement of deferred tax assets in connection with other tax rate changes	$ 1,657	$ (1,353)	$ 0
Remeasurement of deferred tax assets in connection with other tax rate changes, percentage	1.00%	(4.70%)	(0.00%)
Remeasurement of liabilities under tax receivable agreement in connection with the enactment of the TCJA	$ (44,051)	$ 0	$ 0
Remeasurement of tax receivable agreement liability in connection with the enactment of the TCJA, percentage	(27.40%)	(0.00%)	(0.00%)
Other	$ (188)	$ 405	$ 0
Other, percentage	(0.10%)	1.40%	0.00%
Income tax expense	$ 151,409	$ 6,350	$ 3,304
Effective income tax rate, percentage	94.50%	22.30%	51.40%

INCOME TAXES- Schedule of Defer

INCOME TAXES- Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Deferred tax assets:
Investment in partnership	$ 137,449	$ 209,648
Tax Receivable Agreement	43,464	110,022
Deferred rent	571	561
Deferred revenue	59	53
Stock-based compensation	322	331
Net operating loss carryforwards	12,332	7,338
Tax credits	2,328	1,084
Other assets	176	108
Total gross deferred tax assets	196,701	329,145
Valuation allowance	(10,114)	(15,568)
Total deferred tax assets, net of valuation allowance	186,587	313,577
Deferred tax liabilities:
Property and equipment	(673)	(370)
Total gross deferred tax liabilities	(673)	(370)
Net deferred tax assets	$ 185,914	$ 313,207

EARNINGS PER SHARE - Narrative

EARNINGS PER SHARE - Narrative (Details) - Common stock - Class A Common Stock - shares	Feb. 04, 2015	Dec. 30, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issued during the period (in shares)	5,968,841	5,750,000
Issuance of class A common stock in settlement of unit appreciation rights (in shares)		339,306
IPO
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issued during the period (in shares)	5,750,000

EARNINGS PER SHARE - Schedule o

EARNINGS PER SHARE - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 27, 2017	Sep. 27, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 28, 2016	Sep. 28, 2016	Jun. 29, 2016	Mar. 30, 2016	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ (11,032)	$ 7,870	$ 8,184	$ 3,862	$ 5,457	$ 6,789	$ 6,549	$ 3,351	$ 8,884	$ 22,146	$ 3,124
Less: net income attributable to non-controlling interests									9,204	9,700	11,900
Net income (loss) attributable to Shake Shack Inc.	$ (12,463)	$ 4,997	$ 4,879	$ 2,267	$ 3,920	$ 3,766	$ 3,298	$ 1,462	$ (320)	$ 12,446	$ (8,776)
Denominator:
Weighted-average shares of Class A common stock outstanding—basic (shares)									25,876	22,956	13,588
Effect of dilutive securities:
Weighted-average shares of Class A common stock outstanding—diluted (shares)									25,876	23,449	13,588
Earnings per share of Class A common stock—basic (in dollars per share)									$ (0.01)	$ 0.54	$ (0.65)
Earnings per share of Class A common stock—diluted (in dollars per share)									$ (0.01)	$ 0.53	$ (0.65)
Stock options
Effect of dilutive securities:
Restricted Class B units (shares)									0	493	0

EARNINGS PER SHARE - Antidilut

EARNINGS PER SHARE - Antidilutive Securities (Details) (Details) - shares	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares (in shares)	1,719,341	125	2,574,981
Performance Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares (in shares)	124,842	26,860	0
Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares (in shares)	44,476	0	0
Class B Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares (in shares)	10,250,007	11,253,592	16,460,741

SUPPLEMENTAL CASH FLOW INFORM91

SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Cash paid for:
Income taxes, net of refunds	$ 2,261	$ 1,823	$ 416
Interest, net of amounts capitalized	1,106	54	92
Non-cash investing activities:
Accrued purchases of property and equipment	7,526	6,150	4,904
Capitalized landlord assets for leases where we are deemed the accounting owner	10,125	1,985	0
Capitalized equity-based compensation	109	139	0
Non-cash financing activities:
Establishment of liabilities under tax receivable agreement	18,973	100,063	173,090
Accrued distributions payable to non-controlling interest holders	0	607	0
IPO And Organizational Transaction | Class A Common Stock
Non-cash investing activities:
Class A common stock issued	0	0	6
Secondary Offering and Redemption of Units | Class A Common Stock
Non-cash investing activities:
Class A common stock issued	1	5	6
Secondary Offering and Redemption of Units | Class B Common Stock
Non-cash financing activities:
Cancellation of Class B common stock	(1)	(5)	(6)
USC Merger | Class A Common Stock
Non-cash investing activities:
Class A common stock issued	0	0	2
USC Merger | Class B Common Stock
Non-cash financing activities:
Cancellation of Class B common stock	0	0	(2)
Parent Company | IPO And Organizational Transaction | Class A Common Stock
Non-cash investing activities:
Class A common stock issued	0	0	6
Parent Company | IPO And Organizational Transaction | Class B Common Stock
Non-cash financing activities:
Cancellation of Class B common stock	0	0	(6)
Parent Company | Secondary Offering and Redemption of Units | Class A Common Stock
Non-cash investing activities:
Class A common stock issued	4,415	18,944	19,933
Parent Company | Secondary Offering and Redemption of Units | Class B Common Stock
Non-cash financing activities:
Cancellation of Class B common stock	(1)	(5)	(6)
Parent Company | USC Merger | Class A Common Stock
Non-cash investing activities:
Class A common stock issued	0	0	2
Parent Company | USC Merger | Class B Common Stock
Non-cash financing activities:
Cancellation of Class B common stock	$ 0	$ 0	$ (2)

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Details)	May 01, 2017USD ($)	Nov. 30, 2015manager	Dec. 27, 2017USD ($)	Sep. 27, 2017USD ($)	Dec. 31, 2013USD ($)
Loss Contingencies [Line Items]
Litigation settlement, expense	$ 774,000
Percentage of tax benefits due to equity owners			85.00%
Establishment of tax receivable agreement liability			$ 159,373,000
Letter of credit
Loss Contingencies [Line Items]
Renewal term			1 year
Retail site
Loss Contingencies [Line Items]
Letters of credit outstanding			$ 160,000
Office building
Loss Contingencies [Line Items]
Letters of credit outstanding					$ 80,000
Home Office Lease
Loss Contingencies [Line Items]
Letters of credit outstanding				$ 603,000
Former Shake Shack Manager Litigation
Loss Contingencies [Line Items]
Number of former Shake Shack managers | manager		2
Settlement agreement amount funded			$ 750,000
IPO
Loss Contingencies [Line Items]
Percentage of tax benefits due to equity owners			85.00%

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details)	Feb. 04, 2015USD ($)	Dec. 27, 2017USD ($)renewal_option	Dec. 28, 2016USD ($)	Dec. 30, 2015USD ($)
Related Party Transaction [Line Items]
Expenses from transactions with related party		$ 0
Percentage of tax benefits due to equity owners		85.00%
Tax receivable agreement amount paid		$ 4,844,000	$ 0	$ 0
Establishment of liabilities under tax receivable agreement		159,373,000
Payments to noncontrolling interests		2,379,000	1,745,000	0
Member distributions		0		(11,125,000)
Distributions to noncontrolling interests payable			607,000
Daily Provisions
Related Party Transaction [Line Items]
Expenses from transactions with related party		6,000	0
Share Our Strength
Related Party Transaction [Line Items]
Expenses from transactions with related party		20,000
Affiliated Entity
Related Party Transaction [Line Items]
General and administrative expenses		7,000	10,000	157,000
Expenses from transactions with related party		0	1,000
Due from related parties, current		0	0
Charitable campaign flow through		633,000	587,000	504,000
Affiliated Entity | Self insurance health care expense
Related Party Transaction [Line Items]
Expenses from transactions with related party		0	0	146,000
Hudson Yards Sports and Entertainment | Concession income
Related Party Transaction [Line Items]
Expenses from transactions with related party		452,000	309,000	282,000
Due from related parties, current		$ 18,000	11,000
Number of renewal terms | renewal_option		5
Renewal option period		5 years
Madison Square Park Conservancy | Rent Expense
Related Party Transaction [Line Items]
Expenses from transactions with related party		$ 907,000	1,062,000	692,000
Due from MSP conservancy			1,000
Madison Square Park Conservancy | Tenant Improvement Allowance
Related Party Transaction [Line Items]
Due from MSP conservancy		0	200,000
Other revenues		200,000	0	0
Madison Square Park Conservancy | Share Our Strength
Related Party Transaction [Line Items]
Expenses from transactions with related party		148,000	117,000	109,000
Board of Directors Chairman | Mobo Systems, Inc.
Related Party Transaction [Line Items]
Expenses from transactions with related party		80,000	0	8,000
Due from MSP conservancy		0	0
Board of Directors Chairman | Square, Inc
Related Party Transaction [Line Items]
Expenses from transactions with related party		33,000
Due from MSP conservancy		$ 0	0
Parent Company
Related Party Transaction [Line Items]
Percentage of tax benefits due to equity owners		85.00%
Tax receivable agreement amount paid		$ 4,844,000	0	0
Establishment of liabilities under tax receivable agreement		159,373,000	272,482,000
Non- Controlling Interest
Related Party Transaction [Line Items]
Tax receivable agreement amount paid		4,910,000
Members' Equity
Related Party Transaction [Line Items]
Tax receivable agreement amount paid		4,910,000
Payments to noncontrolling interests		$ 2,379,000	$ 1,745,000
Member distributions	$ (11,125,000)			$ (11,125,000)

GEOGRAPHIC INFORMATION (Details

GEOGRAPHIC INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 27, 2017	Sep. 27, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 28, 2016	Sep. 28, 2016	Jun. 29, 2016	Mar. 30, 2016	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 96,136	$ 94,609	$ 91,316	$ 76,749	$ 73,271	$ 74,567	$ 66,472	$ 54,165	$ 358,810	$ 268,475	$ 190,592
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									348,575	260,602	184,408
Other countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									$ 10,235	$ 7,873	$ 6,184

SELECTED QUARTERLY FINANCIAL 95

SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 27, 2017	Sep. 27, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 28, 2016	Sep. 28, 2016	Jun. 29, 2016	Mar. 30, 2016	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Quarterly Financial Information Disclosure [Abstract]
Total revenue	$ 96,136	$ 94,609	$ 91,316	$ 76,749	$ 73,271	$ 74,567	$ 66,472	$ 54,165	$ 358,810	$ 268,475	$ 190,592
Operating income	5,838	10,610	11,737	5,628	4,988	9,170	8,933	4,714	33,813	27,805	6,753
Net income	(11,032)	7,870	8,184	3,862	5,457	6,789	6,549	3,351	8,884	22,146	3,124
Net income attributable to Shake Shack Inc.	$ (12,463)	$ 4,997	$ 4,879	$ 2,267	$ 3,920	$ 3,766	$ 3,298	$ 1,462	$ (320)	$ 12,446	$ (8,776)
Earnings (loss) per share
Basic (in dollars per share)	$ (0.47)	$ 0.19	$ 0.19	$ 0.09	$ 0.16	$ 0.16	$ 0.15	$ 0.07
Diluted (in dollars per share)	$ (0.47)	$ 0.19	$ 0.19	$ 0.09	$ 0.15	$ 0.15	$ 0.14	$ 0.07

SCHEDULE I_ CONDENSED FINANCI96

SCHEDULE I: CONDENSED FINANCIAL INFORMATION OF REGISTRANT - BALANCE SHEET (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015	Feb. 04, 2015	Dec. 31, 2014
Preferred stock, par value (in dollars per share)	$ 0	$ 0
Current assets:
Accounts receivable	$ 5,641	$ 6,006
Total current assets	93,199	83,944
Deferred income taxes, net	185,914	313,207
TOTAL ASSETS	470,606	538,194
Current liabilities:
Accrued expenses	11,649	8,538
Current portion of liabilities under tax receivable agreement	937	4,580
Total current liabilities	34,024	31,716
Liabilities under tax receivable agreement, net of current portion	158,436	267,902
Total liabilities	246,127	336,841
Commitments and contingencies
Stockholders' equity:
Preferred stock, no par value—10,000,000 shares authorized; none issued and outstanding as of December 27, 2017 and December 28, 2016, respectively.	0	0
Additional paid-in capital	153,105	135,448
Retained earnings	16,399	16,719
Accumulated other comprehensive loss	(49)	(15)
Total stockholders' equity	224,479	201,353	$ 157,019		$ 12,600
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 470,606	$ 538,194
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000		10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Class A Common Stock
Stockholders' equity:
Common stock	$ 27	$ 25
Common stock par value (in dollars per share)	$ 0.001	$ 0.001		$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000		200,000,000
Common stock, shares, issued (in shares)	26,527,477	25,151,384
Common stock, shares, outstanding (in shares)	26,527,477	25,151,384
Class B Common Stock
Stockholders' equity:
Common stock	$ 10	$ 11
Common stock par value (in dollars per share)	$ 0.001	$ 0.001		$ 0.001
Common stock, shares authorized (in shares)	35,000,000	35,000,000		35,000,000
Common stock, shares, issued (in shares)	10,250,007	11,253,592
Common stock, shares, outstanding (in shares)	10,250,007	11,253,592
Parent Company
Preferred stock, par value (in dollars per share)	$ 0	$ 0
Current assets:
Cash	$ 4,988	$ 3,785
Accounts receivable	0	2
Prepaid expenses	100	105
Total current assets	5,088	3,892
Deferred income taxes, net	185,750	312,802
Investment in subsidiaries	142,314	109,680
TOTAL ASSETS	333,152	426,374
Current liabilities:
Accrued expenses	70	49
Due to SSE Holdings	4,217	1,655
Current portion of liabilities under tax receivable agreement	937	4,580
Total current liabilities	5,224	6,284
Liabilities under tax receivable agreement, net of current portion	158,436	267,902
Total liabilities	163,660	274,186
Commitments and contingencies
Stockholders' equity:
Preferred stock, no par value—10,000,000 shares authorized; none issued and outstanding as of December 27, 2017 and December 28, 2016, respectively.	0	0
Additional paid-in capital	153,105	135,448
Retained earnings	16,399	16,719
Accumulated other comprehensive loss	(49)	(15)
Total stockholders' equity	169,492	152,188
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 333,152	$ 426,374
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Parent Company | Class A Common Stock
Stockholders' equity:
Common stock	$ 27	$ 25
Common stock par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares, issued (in shares)	26,527,477	25,151,384
Common stock, shares, outstanding (in shares)	26,527,477	25,151,384
Parent Company | Class B Common Stock
Stockholders' equity:
Common stock	$ 10	$ 11
Common stock par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	35,000,000	35,000,000
Common stock, shares, issued (in shares)	10,250,007	11,253,592
Common stock, shares, outstanding (in shares)	10,250,007	11,253,592

SCHEDULE I_ CONDENSED FINANCI97

SCHEDULE I: CONDENSED FINANCIAL INFORMATION OF REGISTRANT - STATEMENTS OF INCOME (LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 27, 2017	Sep. 27, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 28, 2016	Sep. 28, 2016	Jun. 29, 2016	Mar. 30, 2016	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Condensed Income Statements, Captions [Line Items]
TOTAL REVENUE	$ 96,136	$ 94,609	$ 91,316	$ 76,749	$ 73,271	$ 74,567	$ 66,472	$ 54,165	$ 358,810	$ 268,475	$ 190,592
General and administrative expenses									39,003	30,556	37,825
TOTAL EXPENSES									324,997	240,670	183,839
OPERATING INCOME	5,838	10,610	11,737	5,628	4,988	9,170	8,933	4,714	33,813	27,805	6,753
Other income									127,221	688	0
Interest expense									(1,643)	(374)	(332)
INCOME BEFORE INCOME TAXES									160,293	28,496	6,428
Income tax expense									151,409	6,350	3,304
NET INCOME	$ (11,032)	$ 7,870	$ 8,184	$ 3,862	$ 5,457	$ 6,789	$ 6,549	$ 3,351	8,884	22,146	3,124
Parent Company
Condensed Income Statements, Captions [Line Items]
Intercompany revenue									1,466	1,603	1,336
TOTAL REVENUE									1,466	1,603	1,336
General and administrative expenses									1,692	1,603	1,336
TOTAL EXPENSES									1,692	1,603	1,336
OPERATING INCOME									(226)	0	0
Equity in net income of subsidiaries									22,090	16,982	6,906
Other income									127,221	688	0
Interest expense									(50)	(16)	0
INCOME BEFORE INCOME TAXES									149,035	17,654	6,906
Income tax expense									149,355	5,208	2,633
NET INCOME									$ (320)	$ 12,446	$ 4,273

SCHEDULE I_ CONDENSED FINANCI98

SCHEDULE I: CONDENSED FINANCIAL INFORMATION OF REGISTRANT - STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Details) - USD ($)		3 Months Ended								12 Months Ended
		Dec. 27, 2017	Sep. 27, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 28, 2016	Sep. 28, 2016	Jun. 29, 2016	Mar. 30, 2016	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Condensed Statement of Income Captions [Line Items]
Net income		$ (11,032,000)	$ 7,870,000	$ 8,184,000	$ 3,862,000	$ 5,457,000	$ 6,789,000	$ 6,549,000	$ 3,351,000	$ 8,884,000	$ 22,146,000	$ 3,124,000
Available-for-sale Securities:
Change in net unrealized holding (losses)	[1]									(94,000)	(35,000)	(11,000)
Less: reclassification adjustments for net realized losses included in net income	[1]									47,000	19,000	0
OTHER COMPREHENSIVE LOSS, NET OF TAX										(47,000)	(16,000)	(11,000)
COMPREHENSIVE INCOME										8,837,000	22,130,000	3,113,000
Income tax benefit										0	0	0
Parent Company
Condensed Statement of Income Captions [Line Items]
Net income										(320,000)	12,446,000	4,273,000
Available-for-sale Securities:
Change in net unrealized holding (losses)	[1]									(67,000)	(22,000)	(5,000)
Less: reclassification adjustments for net realized losses included in net income	[1]									33,000	12,000	0
OTHER COMPREHENSIVE LOSS, NET OF TAX	[1]									(34,000)	(10,000)	(5,000)
COMPREHENSIVE INCOME										$ (354,000)	12,436,000	4,268,000
Income tax benefit											$ 0	$ 0
[1]	Net of tax benefit of $0 for fiscal years ended December 27, 2017, December 28, 2016 and December 30, 2015.

SCHEDULE I_ CONDENSED FINANCI99

SCHEDULE I: CONDENSED FINANCIAL INFORMATION OF REGISTRANT - STATEMENTS OF CASH FLOWS (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 27, 2017	Sep. 27, 2017	Jun. 28, 2017	Mar. 29, 2017	Dec. 28, 2016	Sep. 28, 2016	Jun. 29, 2016	Mar. 30, 2016	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
OPERATING ACTIVITIES
Net income	$ (11,032,000)	$ 7,870,000	$ 8,184,000	$ 3,862,000	$ 5,457,000	$ 6,789,000	$ 6,549,000	$ 3,351,000	$ 8,884,000	$ 22,146,000	$ 3,124,000
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Equity-based compensation									5,623,000	5,354,000	16,681,000
Deferred income taxes									146,334,000	(523,000)	(734,000)
Other non-cash income									(127,221,000)	(688,000)	0
Changes in operating assets and liabilities:
Accounts receivable									6,421,000	2,974,000	775,000
Prepaid expenses and other current assets									2,244,000	(756,000)	(958,000)
Accrued expenses									4,388,000	5,560,000	2,548,000
Other current liabilities									(988,000)	2,130,000	257,000
NET CASH PROVIDED BY OPERATING ACTIVITIES									70,878,000	54,285,000	41,258,000
INVESTING ACTIVITIES
NET CASH USED IN INVESTING ACTIVITIES									(61,943,000)	(114,761,000)	(34,514,000)
FINANCING ACTIVITIES
Proceeds from issuance of Class A common stock sold in initial public offering, net of underwriting discounts and commissions									0	0	109,262,000
Proceeds from issuance of Class B common stock									0	0	30,000
Proceeds from stock option exercises									7,585,000	3,194,000	0
Payments under tax receivable agreement									(4,844,000)	0	0
NET CASH PROVIDED BY FINANCING ACTIVITIES									965,000	1,234,000	61,428,000
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS									9,900,000	(59,242,000)	68,172,000
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD				11,607,000				70,849,000	11,607,000	70,849,000	2,677,000
CASH AND CASH EQUIVALENTS AT END OF PERIOD	21,507,000				11,607,000				21,507,000	11,607,000	70,849,000
Parent Company
OPERATING ACTIVITIES
Net income									(320,000)	12,446,000	4,273,000
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Equity in net income of subsidiaries									(22,090,000)	(16,982,000)	(6,906,000)
Equity-based compensation									234,000	189,000	330,000
Non-cash reimbursement revenue treated as investment									0	(189,000)	0
Deferred income taxes									146,095,000	(462,000)	(551,000)
Other non-cash income									(127,221,000)	(688,000)	0
Changes in operating assets and liabilities:
Accounts receivable									2,000	(2,000)	0
Prepaid expenses and other current assets									5,000	(1,000)	0
Due to/from SSE Holdings									(5,339,000)	214,000	4,000
Accrued expenses									21,000	(11,000)	58,000
Other current liabilities									(17,000)	17,000	0
Income taxes payable									2,990,000	5,023,000	3,184,000
NET CASH PROVIDED BY OPERATING ACTIVITIES									(5,640,000)	(446,000)	392,000
INVESTING ACTIVITIES
Purchases of LLC Interests from SSE Holdings									(5,522,000)	(4,559,000)	(112,298,000)
Return of investment in SSE Holdings									4,101,000	2,694,000	0
NET CASH USED IN INVESTING ACTIVITIES									(1,421,000)	(1,865,000)	(112,298,000)
FINANCING ACTIVITIES
Proceeds from issuance of Class A common stock sold in initial public offering, net of underwriting discounts and commissions									0	0	112,298,000
Proceeds from issuance of Class A common stock to SSE Holdings upon settlement of stock option exercises									5,522,000	2,489,000	0
Proceeds from issuance of Class B common stock									0	0	30,000
Proceeds from stock option exercises									7,586,000	3,185,000	0
Payments under tax receivable agreement									(4,844,000)	0	0
NET CASH PROVIDED BY FINANCING ACTIVITIES									8,264,000	5,674,000	112,328,000
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS									1,203,000	3,363,000	422,000
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD				$ 3,785,000				$ 422,000	3,785,000	422,000	0
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 4,988,000				$ 3,785,000				$ 4,988,000	$ 3,785,000	$ 422,000

SCHEDULE I_ CONDENSED FINANC100

SCHEDULE I: CONDENSED FINANCIAL INFORMATION OF REGISTRANT - NOTES TO FINANCIAL STATEMENTS (Details) - USD ($)	Feb. 04, 2015	Dec. 30, 2015	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Class of Stock [Line Items]
Percentage of tax benefits due to equity owners			85.00%
Payments under tax receivable agreement			$ (4,844,000)	$ 0	$ 0
Cash paid for:
Income taxes			2,261,000	1,823,000	416,000
Interest			1,106,000	54,000	92,000
Non-cash financing activities:
Establishment of liabilities under tax receivable agreement			$ 159,373,000
IPO
Class of Stock [Line Items]
Percentage of tax benefits due to equity owners			85.00%
Class A Common Stock | USC Merger
Non-cash investing activities:
Class A common stock issued			$ 0	0	2,000
Class A Common Stock | Secondary Offering and Redemption of Units
Non-cash investing activities:
Class A common stock issued			1,000	5,000	6,000
Class A Common Stock | IPO And Organizational Transaction
Non-cash investing activities:
Class A common stock issued			0	0	$ 6,000
Class A Common Stock | Common stock
Class of Stock [Line Items]
Shares issued during the period (in shares)	5,968,841				5,750,000
Class A Common Stock | Common stock | IPO
Class of Stock [Line Items]
Shares issued during the period (in shares)	5,750,000
Shares issued, share price (in dollars per share)	$ 21
Proceeds of issuance of initial public offering net of underwriting discounts and commissions	$ 112,298,000
Class A Common Stock | Common stock | Over-allotment option
Class of Stock [Line Items]
Shares issued during the period (in shares)	750,000
Class A Common Stock | Common stock | USC Merger
Class of Stock [Line Items]
Shares issued during the period (in shares)		1,727,804
Class B Common Stock | USC Merger
Non-cash financing activities:
Cancellation of Class B common stock			0	0	$ (2,000)
Class B Common Stock | Secondary Offering and Redemption of Units
Non-cash financing activities:
Cancellation of Class B common stock			(1,000)	(5,000)	(6,000)
Class B Common Stock | Common stock
Class of Stock [Line Items]
Shares issued during the period (in shares)	30,160,694
Parent Company
Class of Stock [Line Items]
Due to SSE Holdings			4,217,000	1,655,000
Intercompany revenue			1,466,000	1,603,000	1,336,000
Equity in net income of subsidiaries			$ 22,090,000	16,982,000	6,906,000
Percentage of tax benefits due to equity owners			85.00%
Payments under tax receivable agreement			$ (4,844,000)	0	0
Non-cash investing activities:
Accrued contribution related to stock option exercises			7,586,000	1,116,000	0
Non-cash contribution made in connection with equity awards granted to employees of SSE Holdings			5,497,000	5,304,000	2,355,000
Non-cash financing activities:
Establishment of liabilities under tax receivable agreement			159,373,000	272,482,000
Parent Company | Class A Common Stock | USC Merger
Non-cash investing activities:
Class A common stock issued			0	0	2,000
Parent Company | Class A Common Stock | Secondary Offering and Redemption of Units
Non-cash investing activities:
Class A common stock issued			4,415,000	18,944,000	19,933,000
Parent Company | Class A Common Stock | IPO And Organizational Transaction
Non-cash investing activities:
Class A common stock issued			0	0	6,000
Parent Company | Class A Common Stock | Common stock | IPO
Class of Stock [Line Items]
Shares issued during the period (in shares)	5,750,000
Shares issued, share price (in dollars per share)	$ 21
Proceeds of issuance of initial public offering net of underwriting discounts and commissions	$ 112,298,000
Parent Company | Class A Common Stock | Common stock | Over-allotment option
Class of Stock [Line Items]
Shares issued during the period (in shares)	750,000
Parent Company | Class B Common Stock | USC Merger
Non-cash financing activities:
Cancellation of Class B common stock			0	0	(2,000)
Parent Company | Class B Common Stock | Secondary Offering and Redemption of Units
Non-cash financing activities:
Cancellation of Class B common stock			(1,000)	(5,000)	(6,000)
Parent Company | Class B Common Stock | IPO And Organizational Transaction
Non-cash financing activities:
Cancellation of Class B common stock			0	0	(6,000)
Consolidation, Eliminations | Parent Company
Class of Stock [Line Items]
Intercompany revenue			1,466,000	1,603,000
Equity in net income of subsidiaries			22,090,000
Cash paid for:
Income taxes			253,000	576,000	0
Interest			2,000	0	0
Non-cash financing activities:
Establishment of liabilities under tax receivable agreement		$ 173,090,000	$ 18,973,000	$ 100,063,000	$ 173,090,000

SCHEDULE II_ VALUATION AND Q101

SCHEDULE II: VALUATION AND QUALIFYING ACCOUNTS (Details) - Deferred tax asset valuation allowance - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015	Dec. 31, 2014
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 15,568	$ 23,155	$ 0	$ 0
Charged to costs and expenses	0	90	0	0
Charged to other accounts	3,455	1,965	39,700	0
Reductions	(8,909)	9,642	16,545	0
Balance at end of period	10,114	$ 15,568	$ 23,155	$ 0
Reductions related to revaluation of tax reform	$ (4,780)