Note 1 - Basis of Presentation	9 Months Ended
Oct. 01, 2016
Notes to Financial Statements
Basis of Accounting [Text Block]	1. Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements of Littelfuse, Inc. and its subsidiaries (the “company”) have been prepared in accordance with U.S. Generally Accepted Accounting Principles (GAAP) for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and disclosures normally included in the consolidated balance sheet, statements of net income and comprehensive income and cash flows prepared in conformity with U.S. GAAP have been condensed or omitted as permitted by such rules and regulations, although the company believes that the disclosures made are adequate to make the information not misleading. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. Operating results for the periods ended October 1, 2016 are not necessarily indicative of the results that may be expected for the year ending December 31, 2016. For further information, refer to the company’s consolidated financial statements and the notes thereto incorporated by reference in the company’s Annual Report on Form 10-K for the year ended January 2, 2016. The company’s unaudited consolidated statement of income for the three and nine months ended October 1, 2016 include the operating results of PolySwitch business purchased from TE Connectivity Ltd and the TVS Diode/Thyristor/IGBT business purchased from ON Semiconductor Corporation since the acquisition dates of these businesses of March 25, 2016 and August 29, 2016, respectively.

1. Basis of Presentation

The accompanying unaudited Condensed Consolidated Financial Statements of Littelfuse, Inc. and its subsidiaries (the “company”) have been prepared in accordance with U.S.

Generally Accepted Accounting Principles

(GAAP) for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and disclosures normally included in the consolidated balance sheet, statements of net income and comprehensive income and cash flows prepared in conformity with U.S. GAAP have been condensed or omitted as permitted by such rules and regulations, although the company believes that the disclosures made are adequate to make the information not misleading. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. Operating results for the periods ended October 1, 2016 are not necessarily indicative of the results that may be expected for the year ending December 31, 2016. For further information, refer to the company’s consolidated financial statements and the notes thereto incorporated by reference in the company’s Annual Report on Form 10-K for the year ended January 2, 2016.

The company’s unaudited consolidated statement of income for the three and nine months ended October 1, 2016 include the operating results of PolySwitch business purchased from TE Connectivity Ltd

and the TVS Diode/Thyristor/IGBT business purchased from ON Semiconductor Corporation

since the acquisition dates of these businesses of March 25, 2016 and August 29, 2016, respectively.