|**NON-OPERATING INCOME (LOSS) (Tables)**              | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|----------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|**Nonoperating Income (Expense) [Abstract]**          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Schedule of Components of Non-operating Income (Loss) | The components of non-operating income (loss) were as follows:201820172016(In millions)Losses on extinguishment of debt(1)$(24)$—$—Gain on sales of businesses——10Adjustment to gain on sale of business—2—Net income related to intellectual property matters(1)——Other(3)——$(28)$2$10_______________(1)Losses associated with our optional redemption of the entire outstanding$400 millionprincipal amount of our4.4%2020 Notes and$400 millionprincipal amount of our 2021 Notes, the repayment in full of$253 millionin remaining outstanding indebtedness under the5-year tranche of our$1.3 billionsenior unsecured term loan facility and the termination of our 2015 Credit Agreement. SeeNote 11: Credit ArrangementsandNote 12: Debtfor additional information.
|                                                     
|                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Losses on extinguishment of debt(1)                   | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
|Gain on sales of businesses                           | —                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
|Adjustment to gain on sale of business                | —                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
|Net income related to intellectual property matters   | (1                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Other                                                 | (3                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|                                                      | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
|                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|(1)                                                   | Losses associated with our optional redemption of the entire outstanding$400 millionprincipal amount of our4.4%2020 Notes and$400 millionprincipal amount of our 2021 Notes, the repayment in full of$253 millionin remaining outstanding indebtedness under the5-year tranche of our$1.3 billionsenior unsecured term loan facility and the termination of our 2015 Credit Agreement. SeeNote 11: Credit ArrangementsandNote 12: Debtfor additional information.                                                                                                                                                                                                                                                                                                         

X- DefinitionComponents of non operating income (loss)
+ ReferencesNo definition available.
+ Details**Name:**
hrs_ComponentsOfNonOperatingIncomeLossTableTextBlock**Namespace Prefix:**
hrs_**Data Type:**
nonnum:textBlockItemType**Balance Type:**
na**Period Type:**
duration X- ReferencesNo definition available.
+ Details**Name:**
us-gaap_NonoperatingIncomeExpenseAbstract**Namespace Prefix:**
us-gaap_**Data Type:**
xbrli:stringItemType**Balance Type:**
na**Period Type:**
duration