Basis of Presentation and Significant Accounting Policies	9 Months Ended
Sep. 27, 2019
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying unaudited condensed consolidated financial statements, in the opinion of management, include all adjustments (consisting only of normal recurring adjustments) which Harmonic Inc. (“Harmonic,” or the “Company”) considers necessary to present fairly the results of operations for the interim periods covered and the consolidated financial condition of the Company at the date of the balance sheets. This Quarterly Report on Form 10-Q should be read in conjunction with the Company’s audited consolidated financial statements contained in the Company’s Annual Report on Form 10-K, which was filed with the Securities and Exchange Commission (“SEC”) on March 1, 2019 (the “2018 Form 10-K”). The interim results presented herein are not necessarily indicative of the results of operations that may be expected for the full fiscal year ending December 31, 2019, or any other future period. The Company’s fiscal quarters are based on 13-week periods, except for the fourth quarter, which ends on December 31. The condensed consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The condensed consolidated balance sheet as of December 31, 2018 was derived from audited financial statements, and the unaudited condensed consolidated financial statements included herein have been prepared pursuant to the rules and regulations of the SEC for interim reporting. As permitted under those requirements, certain footnotes or other financial information that are normally required by generally accepted accounting principles in the United States of America (“U.S. GAAP”) have been condensed or omitted. Use of Estimates The preparation of the condensed 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 revenue and expenses during the reporting period. The Company’s reported financial positions or results of operations may be materially different under changed conditions or when using different estimates and assumptions, particularly with respect to significant accounting policies. If estimates or assumptions differ from actual results, subsequent periods are adjusted to reflect more current information. Reclassifications Certain prior period balances have been reclassified to conform to the current period’s presentation. These reclassifications did not have a material impact on previously reported financial statements. Beginning in the first quarter of fiscal 2019, the Company revised the classification of total revenue in the Condensed Consolidated Statements of Operations from the two previous categories, “Product” and “Service”, to two new categories, “Appliance and integration” and “SaaS and service”. The Company has also reclassified revenue into the two new categories for all prior periods to conform to the current period’s presentation. This reclassification within revenue did not have an impact on total revenue or any segment revenue for any periods presented. Significant Accounting Policies The Company’s significant accounting policies are described in Note 2 to its audited Consolidated Financial Statements included in the 2018 Form 10-K. There have been no significant changes to these policies during the nine months ended September 27, 2019 other than those disclosed in Note 2, “Recent Accounting Pronouncements”.

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements, in the opinion of management, include all adjustments (consisting only of normal recurring adjustments) which Harmonic Inc. (“Harmonic,” or the “Company”) considers necessary to present fairly the results of operations for the interim periods covered and the consolidated financial condition of the Company at the date of the balance sheets. This Quarterly Report on Form 10-Q should be read in conjunction with the Company’s audited consolidated financial statements contained in the Company’s Annual Report on Form 10-K, which was filed with the Securities and Exchange Commission (“SEC”) on March 1, 2019 (the “2018 Form 10-K”). The interim results presented herein are not necessarily indicative of the results of operations that may be expected for the full fiscal year ending December 31, 2019, or any other future period. The Company’s fiscal quarters are based on 13-week periods, except for the fourth quarter, which ends on December 31.

The condensed consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The condensed consolidated balance sheet as of December 31, 2018 was derived from audited financial statements, and the unaudited condensed consolidated financial statements included herein have been prepared pursuant to the rules and regulations of the SEC for interim reporting. As permitted under those requirements, certain footnotes or other financial information that are normally required by generally accepted accounting principles in the United States of America (“U.S. GAAP”) have been condensed or omitted.

Use of Estimates

The preparation of the condensed 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 revenue and expenses during the reporting period. The Company’s reported financial positions or results of operations may be materially different under changed conditions or when using different estimates and assumptions, particularly with respect to significant accounting policies. If estimates or assumptions differ from actual results, subsequent periods are adjusted to reflect more current information.

Reclassifications

Certain prior period balances have been reclassified to conform to the current period’s presentation. These reclassifications did not have a material impact on previously reported financial statements.

Beginning in the first quarter of fiscal 2019, the Company revised the classification of total revenue in the Condensed Consolidated Statements of Operations from the two previous categories, “Product” and “Service”, to two new categories, “Appliance and integration” and “SaaS and service”. The Company has also reclassified revenue into the two new categories for all prior periods to conform to the current period’s presentation. This reclassification within revenue did not have an impact on total revenue or any segment revenue for any periods presented.

Significant Accounting Policies

The Company’s significant accounting policies are described in Note 2 to its audited Consolidated Financial Statements included in the 2018 Form 10-K. There have been no significant changes to these policies during the nine months ended September 27, 2019 other than those disclosed in Note 2, “Recent Accounting Pronouncements”.