Business and Basis of Presentation (Policies)	6 Months Ended
Jan. 01, 2017
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 two quarters ended January 1, 2017 are not necessarily indicative of the results that may be expected for the year ending July 2, 2017. The consolidated balance sheet at July 3, 2016 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 3, 2016. The Company reports fiscal years on a 52-53 week year (5-4-4 basis) ending on the Sunday closest to June 30. On April 27, 2016, Sparton announced that its Board of Directors had authorized a process to identify parties interested in acquiring the Company. This process is ongoing and there can be no assurance that this process will result in a consummation of any transaction. The Company cannot currently determine if the process will ultimately conclude in a sale of all or some of its assets. As such, no adjustments have been made to the Company’s carrying value of its assets or liabilities as a result of the contemplated sale.
New Accounting Standards	New Accounting Standards In May 2014, the FASB issued Accounting Standards Update No. 2014-09 ("ASU 2014-09"), Revenue from Contracts with Customers, which amends guidance for revenue recognition. Under the new standard, revenue will be recognized when control of the promised goods or services is transferred to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods and services. The standard creates a five-step model that will generally require companies to use more judgment and make more estimates than under current guidance when considering the terms of contracts along with all relevant facts and circumstances. These include the identification of customer contracts and separating performance obligations, the determination of transaction price that potentially includes an estimate of variable consideration, allocating the transaction price to each separate performance obligation, and recognizing revenue in line with the pattern of transfer. In August 2015, the FASB issued an amendment to defer the effective date for all entities by one year. The new standard will become effective for annual reporting periods beginning after December 15, 2017, including interim periods within that reporting period. Early adoption is permitted as of annual reporting periods beginning after December 15, 2016. Companies have the option of using either a full or modified retrospective approach in applying this standard. During fiscal 2016, the FASB issued three additional updates which further clarify the guidance provided in ASU 2014-09. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements. In July 2015, the FASB issued Accounting Standards Update No. 2015-11 ("ASU 2015-11"), Simplifying the Measurement of Inventory. ASU 2015-11 clarifies that inventory should be held at the lower of cost or net realizable value. Net realizable value is defined as the estimated selling price, less the estimated costs to complete, dispose and transport such inventory. ASU 2015-11 will be effective for fiscal years and interim periods beginning after December 15, 2016. ASU 2015-11 is required to be applied prospectively and early adoption is permitted. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements. In February 2016, the FASB issued Accounting Standards Update No. 2016-02 (“ASU 2016-02”), Leases (Topic 842). ASU 2016-02 establishes a right-of-use (ROU) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. A modified retrospective transition approach is required for capital leases and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update No. 2016-09 ("ASU 2016-09"), Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. ASU 2016-09 will directly impact the tax administration of equity plans. ASU 2016-09 is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted and any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. The Company has elected to early adopt ASU 2016-09 as of July 4, 2016 on a prospective basis. There was no impact on the Company's financial statements as a result of early adoption in the first quarter of fiscal year 2017. In June 2016, the FASB issued Accounting Standards Update No. 2016-13 ("ASU 2016-13"), Financial Instruments—Credit Losses (Topic 326). ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. ASU 2016-13 is effective for fiscal years beginning after December 15, 2019 and early adoption is permitted. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements. In August 2016, the FASB issued Accounting Standards Update No. 2016-15 ("ASU 2016-15"), Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 will make eight targeted changes to how cash receipts and cash payments are presented and classified in the statement of cash flows. ASU 2016-15 is effective for fiscal years beginning after December 15, 2017. The new standard will require adoption on a retrospective basis unless it is impracticable to apply, in which case it would be required to apply the amendments prospectively as of the earliest date practicable. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements. In October 2016, the FASB issued ASU 2016-16 ("ASU 2016-16"), Income Taxes - Intra-Entity Transfers of Assets Other Than Inventory, which requires entities to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. ASU 2016-16 is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted as of the beginning of a fiscal year. ASU 2016-16 must be adopted using a modified retrospective transition method which is a cumulative-effective adjustment to retained earnings as of the beginning of the first effective reporting period. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements. In November 2016, The FASB issued ASU No. 2016-18 ("ASU 2016-18"), Restricted Cash, which addresses classification and presentation of changes in restricted cash on the statement of cash flows. ASU 2016-18 requires an entity’s reconciliation of the beginning-of-period and end-of-period total amounts shown on the statement of cash flows to include in cash and cash equivalents amounts generally described as restricted cash and restricted cash equivalents. ASU 2016-18 does not define restricted cash or restricted cash equivalents, but an entity will need to disclose the nature of the restrictions. ASU 2016-18 is effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2017. Early adoption is permitted, including adoption in an interim period. If an entity early adopts the amendments in an interim period, adjustments should be reflected at the beginning of the fiscal year that includes that interim period. Entities should apply this ASU using a retrospective transition method to each period presented. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements.

New Accounting Standards

In May 2014, the FASB issued Accounting Standards Update No. 2014-09 ("ASU 2014-09"), Revenue from Contracts with Customers, which amends guidance for revenue recognition. Under the new standard, revenue will be recognized when control of the promised goods or services is transferred to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods and services. The standard creates a five-step model that will generally require companies to use more judgment and make more estimates than under current guidance when considering the terms of contracts along with all relevant facts and circumstances. These include the identification of customer contracts and separating performance obligations, the determination of transaction price that potentially includes an estimate of variable consideration, allocating the transaction price to each separate performance obligation, and recognizing revenue in line with the pattern of transfer. In August 2015, the FASB issued an amendment to defer the effective date for all entities by one year. The new standard will become effective for annual reporting periods beginning after December 15, 2017, including interim periods within that reporting period. Early adoption is permitted as of annual reporting periods beginning after December 15, 2016. Companies have the option of using either a full or modified retrospective approach in applying this standard. During fiscal 2016, the FASB issued three additional updates which further clarify the guidance provided in ASU 2014-09. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements.

In July 2015, the FASB issued Accounting Standards Update No. 2015-11 ("ASU 2015-11"), Simplifying the Measurement of Inventory. ASU 2015-11 clarifies that inventory should be held at the lower of cost or net realizable value. Net realizable value is defined as the estimated selling price, less the estimated costs to complete, dispose and transport such inventory. ASU 2015-11 will be effective for fiscal years and interim periods beginning after December 15, 2016. ASU 2015-11 is required to be applied prospectively and early adoption is permitted. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements.

In February 2016, the FASB issued Accounting Standards Update No. 2016-02 (“ASU 2016-02”), Leases (Topic 842). ASU 2016-02 establishes a right-of-use (ROU) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. A modified retrospective transition approach is required for capital leases and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements.

In March 2016, the FASB issued Accounting Standards Update No. 2016-09 ("ASU 2016-09"), Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. ASU 2016-09 will directly impact the tax administration of equity plans. ASU 2016-09 is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted and any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. The Company has elected to early adopt ASU 2016-09 as of July 4, 2016 on a prospective basis. There was no impact on the Company's financial statements as a result of early adoption in the first quarter of fiscal year 2017.

In June 2016, the FASB issued Accounting Standards Update No. 2016-13 ("ASU 2016-13"), Financial Instruments—Credit Losses (Topic 326). ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. ASU 2016-13 is effective for fiscal years beginning after December 15, 2019 and early adoption is permitted. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements.

In August 2016, the FASB issued Accounting Standards Update No. 2016-15 ("ASU 2016-15"), Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 will make eight targeted changes to how cash receipts and cash payments are presented and classified in the statement of cash flows. ASU 2016-15 is effective for fiscal years beginning after December 15, 2017. The new standard will require adoption on a retrospective basis unless it is impracticable to apply, in which case it would be required to apply the amendments prospectively as of the earliest date practicable. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements.

In October 2016, the FASB issued ASU 2016-16 ("ASU 2016-16"), Income Taxes - Intra-Entity Transfers of Assets Other Than Inventory, which requires entities to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. ASU 2016-16 is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted as of the beginning of a fiscal year. ASU 2016-16 must be adopted using a modified retrospective transition method which is a cumulative-effective adjustment to retained earnings as of the beginning of the first effective reporting period. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements.

In November 2016, The FASB issued ASU No. 2016-18 ("ASU 2016-18"), Restricted Cash, which addresses classification and presentation of changes in restricted cash on the statement of cash flows. ASU 2016-18 requires an entity’s reconciliation of the beginning-of-period and end-of-period total amounts shown on the statement of cash flows to include in cash and cash equivalents amounts generally described as restricted cash and restricted cash equivalents. ASU 2016-18 does not define restricted cash or restricted cash equivalents, but an entity will need to disclose the nature of the restrictions. ASU 2016-18 is effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2017. Early adoption is permitted, including adoption in an interim period. If an entity early adopts the amendments in an interim period, adjustments should be reflected at the beginning of the fiscal year that includes that interim period. Entities should apply this ASU using a retrospective transition method to each period presented. The Company is currently in the process of evaluating the impact of adoption on its consolidated financial statements.