Business and Basis of Presentation	9 Months Ended
Apr. 01, 2018
Accounting Policies [Abstract]
Business and Basis of Presentation	Business and Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Certain reclassifications of prior year amounts have been made to conform to the current year presentation. Subsequent events have been evaluated through the date these financial statements were issued. Additionally, the consolidated financial statements should be read in conjunction with Item 2, Management’s Discussion and Analysis of Financial Condition and Results of Operations, included in this Quarterly Report on Form 10-Q. Operating results for the quarter and three quarters ended April 1, 2018 are not necessarily indicative of the results that may be expected for the year ending July 1, 2018. The consolidated balance sheet at July 2, 2017 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States ("GAAP") for complete financial statements. For further information, refer to the consolidated financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended July 2, 2017. The Company reports fiscal years on a 52-53 week year (5-4-4 basis) ending on the Sunday closest to June 30. On July 7, 2017, Sparton Corporation (the "Company" or "Sparton"), Ultra Electronics Holdings plc, (“Ultra”), and Ultra Electronics Aneira Inc., (“Merger Sub”) entered into an Agreement and Plan of Merger (the "Merger Agreement") that provided for Ultra to acquire the Company by merging Merger Sub into the Company (such transaction referred to as the "Merger"), subject to the terms and conditions set forth in the Merger Agreement. On October 5, 2017, at a special meeting of holders of shares of common stock of the Company, shareholders voted to adopt the Merger Agreement. Although the Merger Agreement had been adopted by the Company's shareholders, consummation of the Merger remained subject to other closing conditions, including the expiration or termination of the applicable waiting period (or any extension thereof) under the Hart-Scott-Rodino Antitrust Improvements Act (the “HSR Act”). On March 5, 2018, Sparton announced the termination by Sparton and Ultra of the Merger Agreement as a result of the staff of the United States Department of Justice (the “DOJ”) informing the parties that it intended to recommend that the DOJ block the Merger. Under a Merger Termination Agreement entered into by Sparton, Ultra and Merger Sub, the parties agreed to release each other from certain claims and liabilities arising out of or related to the Merger Agreement or the transactions contemplated therein or thereby, including any termination fees. The parties also agreed that certain agreements with confidentiality obligations will continue in full force and effect. Also on March 5, 2018, Sparton announced that, during the DOJ’s review of Sparton’s proposed Merger with Ultra, the United States Navy (the “Navy”) expressed the view that instead of the parties proceeding with the Merger, each of Sparton and Ultra should enhance its ability to independently develop, produce and sell sonobuoys and over time work toward the elimination of their use of Sparton’s and Ultra’s joint venture for such activities. Since that time, Sparton has been in communication with the Navy to better understand its expectations with respect to the timing, funding and terms of current and future sonobuoy IDIQ production contracts. While no deadlines have been established nor funding decisions agreed upon, we believe the Navy would find it desirable if Sparton and Ultra were in a position to eliminate the use of the ERAPSCO joint venture for the sale of sonobuoys to the Navy by September, 2024, which is the end of the GFY19-GFY23 IDIQ contract. Due to the significance of the effort and expenditures required, there can be no assurance that Sparton, or both of the ERAPSCO joint venture partners, will be able to independently develop, produce and sell fully qualified sonobuoys by that time, or at an earlier date if so required by the Navy. The GFY19-GFY23 IDIQ contract is currently under evaluation and we anticipate that an award will be made by the Navy in GFY19 and that final delivery will be scheduled to occur in 2024. Additionally, we understand that there will be no impact on the existing GFY14-GFY18 IDIQ contract which provides for final delivery to occur in 2019. As a result of the termination of the Merger Agreement, the Company announced that it will seek to re-engage with parties that previously expressed an interest in acquiring all or a part of Sparton and that are in a position to expeditiously proceed to effect such a transaction. The Company is currently in active discussions with interested parties. There can be no assurance these discussions will result in the execution of a definitive agreement or the completion of a transaction.

Business and Basis of Presentation

The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Certain reclassifications of prior year amounts have been made to conform to the current year presentation. Subsequent events have been evaluated through the date these financial statements were issued. Additionally, the consolidated financial statements should be read in conjunction with Item 2, Management’s Discussion and Analysis of Financial Condition and Results of Operations, included in this Quarterly Report on Form 10-Q. Operating results for the quarter and three quarters ended April 1, 2018 are not necessarily indicative of the results that may be expected for the year ending July 1, 2018. The consolidated balance sheet at July 2, 2017 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States ("GAAP") for complete financial statements. For further information, refer to the consolidated financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended July 2, 2017.

The Company reports fiscal years on a 52-53 week year (5-4-4 basis) ending on the Sunday closest to June 30.

On July 7, 2017, Sparton Corporation (the "Company" or "Sparton"), Ultra Electronics Holdings plc, (“Ultra”), and Ultra Electronics Aneira Inc., (“Merger Sub”) entered into an Agreement and Plan of Merger (the "Merger Agreement") that provided for Ultra to acquire the Company by merging Merger Sub into the Company (such transaction referred to as the "Merger"), subject to the terms and conditions set forth in the Merger Agreement.

On October 5, 2017, at a special meeting of holders of shares of common stock of the Company, shareholders voted to adopt the Merger Agreement. Although the Merger Agreement had been adopted by the Company's shareholders, consummation of the Merger remained subject to other closing conditions, including the expiration or termination of the applicable waiting period (or any extension thereof) under the Hart-Scott-Rodino Antitrust Improvements Act (the “HSR Act”).

On March 5, 2018, Sparton announced the termination by Sparton and Ultra of the Merger Agreement as a result of the staff of the United States Department of Justice (the “DOJ”) informing the parties that it intended to recommend that the DOJ block the Merger. Under a Merger Termination Agreement entered into by Sparton, Ultra and Merger Sub, the parties agreed to release each other from certain claims and liabilities arising out of or related to the Merger Agreement or the transactions contemplated therein or thereby, including any termination fees. The parties also agreed that certain agreements with confidentiality obligations will continue in full force and effect.

Also on March 5, 2018, Sparton announced that, during the DOJ’s review of Sparton’s proposed Merger with Ultra, the United States Navy (the “Navy”) expressed the view that instead of the parties proceeding with the Merger, each of Sparton and Ultra should enhance its ability to independently develop, produce and sell sonobuoys and over time work toward the elimination of their use of Sparton’s and Ultra’s joint venture for such activities. Since that time, Sparton has been in communication with the Navy to better understand its expectations with respect to the timing, funding and terms of current and future sonobuoy IDIQ production contracts. While no deadlines have been established nor funding decisions agreed upon, we believe the Navy would find it desirable if Sparton and Ultra were in a position to eliminate the use of the ERAPSCO joint venture for the sale of sonobuoys to the Navy by September, 2024, which is the end of the GFY19-GFY23 IDIQ contract. Due to the significance of the effort and expenditures required, there can be no assurance that Sparton, or both of the ERAPSCO joint venture partners, will be able to independently develop, produce and sell fully qualified sonobuoys by that time, or at an earlier date if so required by the Navy. The GFY19-GFY23 IDIQ contract is currently under evaluation and we anticipate that an award will be made by the Navy in GFY19 and that final delivery will be scheduled to occur in 2024. Additionally, we understand that there will be no impact on the existing GFY14-GFY18 IDIQ contract which provides for final delivery to occur in 2019.

As a result of the termination of the Merger Agreement, the Company announced that it will seek to re-engage with parties that previously expressed an interest in acquiring all or a part of Sparton and that are in a position to expeditiously proceed to effect such a transaction. The Company is currently in active discussions with interested parties. There can be no assurance these discussions will result in the execution of a definitive agreement or the completion of a transaction.