Business Divestitures and Assets Sales (Details) - USD ($)						3 Months Ended			6 Months Ended
	May 15, 2020	May 04, 2020	Mar. 20, 2020	Jan. 31, 2020	Sep. 13, 2019	Jul. 03, 2020	Sep. 27, 2019	Jun. 28, 2019	Jul. 03, 2020	Jun. 28, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from sale of business, after selling costs and estimated price adjustments									$ 963,000,000	$ 0
Non-cash goodwill impairment charge							$ 0		369,000,000
Non-cash remeasurement loss recognized on remaining assets of disposal group									14,000,000
Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash goodwill impairment charge									364,000,000
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
Communication Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash goodwill impairment charge									0
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]
Non-cash goodwill impairment charge				$ 0
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]
Cash price on sale of business		$ 1,000,000,000
Cash proceeds from sale of business, after selling costs and estimated price adjustments		951,000,000
Pre-tax (loss) gain on sale of disposal group		(26,000,000)
(Loss) income before taxes of disposal group						$ (3,000,000)			9,000,000
Goodwill assigned to disposal group		$ 531,000,000
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]
Cash price on sale of business	$ 12,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Harris Night Vision | L3Harris
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from sale of business, after selling costs and estimated price adjustments					$ 343,000,000
Pre-tax (loss) gain on sale of disposal group					229,000,000
(Loss) income before taxes of disposal group								$ 8,000,000		$ 14,000,000
Non-cash adjustment to gain on sale of business						12,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Harris Night Vision | Other non-reportable business segments | L3Harris
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash price on sale of business					$ 350,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | EOTech Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets of disposal group held for sale						46,000,000			46,000,000
Liabilities of disposal group held for sale						7,000,000			7,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | EOTech Business | Communication 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 | EOTech Business | Communication Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash price on sale of business			$ 42,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | Other AS Disposal Groups | Aviation Systems
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash goodwill impairment charge						14,000,000
Total loss recognized to reduce fair value of assets of disposal group						28,000,000
Non-cash remeasurement loss recognized on remaining assets of disposal group						14,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | Other AS Disposal Groups | 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			14,000,000
Assets of disposal group held for sale						42,000,000			42,000,000
Liabilities of disposal group held for sale						$ 14,000,000			$ 14,000,000