| **Intangible Assets**                                      | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
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| **Intangible Assets, Net (Excluding Goodwill) [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| INTANGIBLE ASSETS                                          | INTANGIBLE ASSETSWe assess the recoverability of the carrying value of our long-lived assets, including intangible assets with finite useful lives, whenever events or changes in circumstances indicate the carrying amount of the assets may not be recoverable.Intangible assets are summarized below: 2016 2015 GrossCarryingAmount AccumulatedAmortization Net GrossCarryingAmount AccumulatedAmortization Net             (In millions)Customer relationships$1,527 $195 $1,332 $1,718 $203 $1,515Developed technologies244 86 158 253 67 186Contract backlog55 55 — 49 48 1Trade names64 20 44 81 22 59Other40 32 8 37 23 14Total intangible assets$1,930 $388 $1,542 $2,138 $363 $1,775Amortization expense related to intangible assets was $167 million, $68 million and $59 million in fiscal 2016, 2015 and 2014, respectively. Fiscal 2016 and fiscal 2015 include approximately $132 million and $11 million, respectively, of amortization expense for intangible assets related to our acquisition of Exelis.In the second quarter of fiscal 2016, we recorded a non-cash impairment charge of $44 million related to intangible assets, related to Harris CapRock Communications (which is part of our Critical Networks segment) due to the downturn in the energy market and its impact on customer operations. This non-cash charge is presented in the “Impairment of goodwill and other assets” line item in our Consolidated Statement of Income. In the fourth quarter of fiscal 2015, we recorded impairment charges totaling $38 million related to long-lived assets included in the “Impairment of goodwill and other assets” line item in our Consolidated Statement of Income. These charges included impairments in our former Integrated Network Solutions segment and what is now our Critical Networks segment related to an intangible asset associated with the Navy/Marine Corps Intranet (“NMCI”) program due to the loss of the contract and the inability to obtain replacement work on the successor program to the NMCI program (the Next Generation Enterprise Network program); and related to fixed assets in Harris CapRock Communications due to a combination of soft market conditions and obsolescence; and impairments of capitalized software acquired in connection with our acquisition of Exelis based on our decision to use alternative software.Future estimated amortization expense for intangible assets is as follows: Total (In millions)Fiscal Years: 2017$1612018148201914420201302021130Thereafter829  Total$1,542   |

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| - Definition
The entire disclosure for all or part of the information related to intangible assets.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275
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| - References
No definition available.
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