Note 1 - Basis of Presentation	3 Months Ended
Apr. 02, 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 period ended April 2, 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 Condensed Consolidated Financial Statements as of April 2, 2016 include the opening balance sheet for the PolySwitch business but do not include any income statement activity of the acquired business as the operating results are not material to the company's financial statements for the three months ended April 2, 2016. The operating results of PolySwitch for the nine day period of March 25, 2016 through April 2, 2016 will be included within the company’s statement of income for the quarter ended July 2, 2016.

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 period ended April 2, 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 Condensed Consolidated Financial Statements as of April 2, 2016 include the opening balance sheet for the PolySwitch business but do not include any income statement activity of the acquired business as the operating results are not material to the company's financial statements for the three months ended April 2, 2016. The operating results of PolySwitch for the nine day period of March 25, 2016 through April 2, 2016 will be included within the company’s statement of income for the quarter ended July 2, 2016.