Business Divestitures - Narrative (Details) - USD ($)				3 Months Ended		12 Months Ended
	Jul. 31, 2020	May 15, 2020	May 04, 2020	Apr. 02, 2021	Apr. 03, 2020	Jan. 01, 2021	Mar. 01, 2021	Feb. 27, 2021	Feb. 23, 2021	Jul. 03, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Pre-tax loss recognized to reduce fair value of assets of disposal group				$ 62,000,000	$ 5,000,000
Non-cash goodwill impairment charge				62,000,000	301,000,000
Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash goodwill impairment charge				62,000,000	296,000,000
Communication Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash goodwill impairment charge				0	0
Space and Airborne Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash goodwill impairment charge				0	5,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | CPS Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill assigned to disposal group				112,000,000
Assets of disposal group held for sale				386,000,000
Liabilities of disposal group held for sale				35,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | CPS Business | Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill assigned to disposal group				174,000,000
Pre-tax loss recognized to reduce fair value of assets of disposal group				69,000,000
Non-cash goodwill impairment charge				62,000,000
Non-cash remeasurement loss recognized on remaining assets of disposal group				7,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | CPS Business | Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds from sale of business							$ 398,000,000
Income before taxes of disposal group				26,000,000	16,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | Military Training Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill assigned to disposal group				426,000,000
Assets of disposal group held for sale				998,000,000
Liabilities of disposal group held for sale				127,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | Military Training Business | Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash goodwill impairment charge				0
Disposal Group, Held-for-sale, Not Discontinued Operations | Military Training Business | Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds from sale of business								$ 1,050,000,000
Income before taxes of disposal group				16,000,000	24,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | VSE Disposal Group | Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill assigned to disposal group										$ 14,000,000
Pre-tax loss recognized to reduce fair value of assets of disposal group				8,000,000		$ 32,000,000
Non-cash goodwill impairment charge						14,000,000
Non-cash remeasurement loss recognized on remaining assets of disposal group						18,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | VSE Disposal Group | Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds from sale of business									$ 20,000,000
Assets of disposal group held for sale				30,000,000		35,000,000
Liabilities of disposal group held for sale				$ 11,000,000		$ 13,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | EOTech Business | Communication Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds from sale of business	$ 42,000,000
Net cash proceeds from sale of business, after selling costs and estimated price adjustments	$ 40,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Applied Kilovolts and Analytical Instrumentation Business | Space and Airborne Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash goodwill impairment charge					5,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Applied Kilovolts and Analytical Instrumentation Business | Space and Airborne Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds from sale of business, after selling costs and estimated price adjustments		$ 12,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Airport Security and Automation Business | Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds from sale of business			$ 1,000,000,000
Income before taxes of disposal group					$ 12,000,000
Net cash proceeds from sale of business, after selling costs and estimated price adjustments			$ 987,000,000