Summary of Significant Accounting Policies	6 Months Ended
Jun. 29, 2014
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation—The consolidated balance sheet data as of December 29, 2013 was derived from audited financial statements. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") for unaudited condensed consolidated financial information. The financial information as of December 29, 2013 is derived from the Company's audited consolidated financial statements and notes included in Item 8 in the Company's Annual Report on Form 10-K for the fiscal year ended December 29, 2013 (the "2013 Form 10-K"), filed with the U.S. Securities and Exchange Commission on February 28, 2014. The financial information included in this Quarterly Report should be read in conjunction with management's discussion and analysis of financial condition and results of operations and the consolidated financial statements and notes included in the 2013 Form 10-K. Accordingly, we have omitted certain footnotes and other disclosures that are disclosed in the 2013 Form 10-K. The accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments which, in the opinion of management, are necessary for a fair presentation of the Company's financial position and results of its operations, as of and for the periods presented. Operating results for the three and six months ended June 29, 2014 are not necessarily indicative of the results that may be expected for the fiscal year ending December 28, 2014, or for any other period. Principles of Consolidation—The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiary, Zulily UK Ltd. All intercompany transactions and balances are eliminated in consolidation. Reclassifications—Certain reclassifications have been made to the condensed consolidated financial statements in the prior period to conform to the current period presentation. Specifically, merchandise deposits are included in prepaid expenses and other current assets as of June 29, 2014 and December 29, 2013. As of December 29, 2013, we reclassified $0.5 million related to merchandise deposits to prepaid expenses and other current assets. Fiscal Year—In 2011, the Company adopted a retail calendar whereby the fiscal year ends on the Sunday closest to December 31. Each fiscal year consists of four 13-week quarters, with one extra week added in the fourth quarter every five to six years. Accounting Estimates—The preparation of unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the result of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results could differ materially from those estimates. Certain Risks and Concentrations—The Company maintains the majority of its cash and cash equivalents in accounts with major financial institutions within the United States, generally in the form of demand and money market accounts. Deposits in these institutions may exceed federally insured limits. The Company has not experienced any losses on its deposits of cash and cash equivalents. The Company is subject to certain risks and concentrations, including dependence on third-party technology providers and hosting services, exposure to risks associated with online commerce security, consumer credit risk, and credit card fraud, as well as the interpretation of state and local laws and regulations in regards to the collection and remittance of sales and use taxes and occupancy taxes. The Company also depends upon third-party service providers for processing customer orders. Recent Accounting Pronouncements—In July 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update No. 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar tax Loss, or a Tax Credit Carryforward Exists ("ASU 2013-11"). The amendments in this update require an unrecognized tax benefit, or a portion of an unrecognized tax benefit, to be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward, except as follows: To the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. The assessment of whether a deferred tax asset is available is based on the unrecognized tax benefit and deferred tax asset that exist at the reporting date and should be made presuming disallowance of the tax position at the reporting date. The amendments in this update do not require new recurring disclosures. For public entities, ASU 2013-11 is effective for annual and interim periods beginning after December 15, 2013. The Company adopted ASU 2013-11 in the first quarter of 2014 and it did not have a material impact on our consolidated financial statements or related disclosures. In May 2014, the Financial Accounting Standards Board (“FASB”) issued an Accounting Standard Update No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”) amending revenue recognition guidance and requiring more detailed disclosures to enable users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. The guidance is effective for annual and interim reporting periods beginning after December 15, 2016, with early adoption prohibited. We are currently evaluating the impact this ASU will have on our consolidated financial statements.

Summary of Significant Accounting Policies

Basis of Presentation—The consolidated balance sheet data as of December 29, 2013 was derived from audited financial statements. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") for unaudited condensed consolidated financial information. The financial information as of December 29, 2013 is derived from the Company's audited consolidated financial statements and notes included in Item 8 in the Company's Annual Report on Form 10-K for the fiscal year ended December 29, 2013 (the "2013 Form 10-K"), filed with the U.S. Securities and Exchange Commission on February 28, 2014. The financial information included in this Quarterly Report should be read in conjunction with management's discussion and analysis of financial condition and results of operations and the consolidated financial statements and notes included in the 2013 Form 10-K. Accordingly, we have omitted certain footnotes and other disclosures that are disclosed in the 2013 Form 10-K. The accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments which, in the opinion of management, are necessary for a fair presentation of the Company's financial position and results of its operations, as of and for the periods presented. Operating results for the three and six months ended June 29, 2014 are not necessarily indicative of the results that may be expected for the fiscal year ending December 28, 2014, or for any other period.

Principles of Consolidation—The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiary, Zulily UK Ltd. All intercompany transactions and balances are eliminated in consolidation.

Reclassifications—Certain reclassifications have been made to the condensed consolidated financial statements in the prior period to conform to the current period presentation. Specifically, merchandise deposits are included in prepaid expenses and other current assets as of June 29, 2014 and December 29, 2013. As of December 29, 2013, we reclassified $0.5 million related to merchandise deposits to prepaid expenses and other current assets.

Fiscal Year—In 2011, the Company adopted a retail calendar whereby the fiscal year ends on the Sunday closest to December 31. Each fiscal year consists of four 13-week quarters, with one extra week added in the fourth quarter every five to six years.

Accounting Estimates—The preparation of unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the result of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results could differ materially from those estimates.

Certain Risks and Concentrations—The Company maintains the majority of its cash and cash equivalents in accounts with major financial institutions within the United States, generally in the form of demand and money market accounts. Deposits in these institutions may exceed federally insured limits. The Company has not experienced any losses on its deposits of cash and cash equivalents.

The Company is subject to certain risks and concentrations, including dependence on third-party technology providers and hosting services, exposure to risks associated with online commerce security, consumer credit risk, and credit card fraud, as well as the interpretation of state and local laws and regulations in regards to the collection and remittance of sales and use taxes and occupancy taxes. The Company also depends upon third-party service providers for processing customer orders.

Recent Accounting Pronouncements—In July 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update No. 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar tax Loss, or a Tax Credit Carryforward Exists ("ASU 2013-11"). The amendments in this update require an unrecognized tax benefit, or a portion of an unrecognized tax benefit, to be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward, except as follows: To the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. The assessment of whether a deferred tax asset is available is based on the unrecognized tax benefit and deferred tax asset that exist at the reporting date and should be made presuming disallowance of the tax position at the reporting date. The amendments in this update do not require new recurring disclosures. For public entities, ASU 2013-11 is effective for annual and interim periods beginning after December 15, 2013. The Company adopted ASU 2013-11 in the first quarter of 2014 and it did not have a material impact on our consolidated financial statements or related disclosures.

In May 2014, the Financial Accounting Standards Board (“FASB”) issued an Accounting Standard Update No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”) amending revenue recognition guidance and requiring more detailed disclosures to enable users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. The guidance is effective for annual and interim reporting periods beginning after December 15, 2016, with early adoption prohibited. We are currently evaluating the impact this ASU will have on our consolidated financial statements.