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Debt Covenant, Customary Event of Default, Failure to Pay Principal Period

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Debt Instrument, Required Notice, Number of Trustee or Holders of Outstanding Principal Amount, Percent

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Debt Issuance Costs And Discounts.

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Make Whole Redemption Price

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Offered repurchase price of notes in percentage of aggregate principal amount of notes.

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Percentage of principal amount of notes for calculation of make whole redemption price.

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Redemption of debentures.

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Repurchased and retired principal amount of debentures.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of principal amount of debt redeemed.

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Amount, after accumulated amortization, of debt premium.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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LONG-TERM DEBT - Fixed Rate Debt (Details) $ in Millions						3 Months Ended		12 Months Ended
LONG-TERM DEBT - Fixed Rate Debt (Details) $ in Millions	Jul. 01, 2015	May 29, 2015 USD ($)	Apr. 27, 2015 USD ($)	Jun. 09, 2009 USD ($)	Dec. 05, 2007 USD ($)	Dec. 30, 2016 USD ($)	Jul. 03, 2015 USD ($)	Jun. 30, 2017 USD ($)	Jul. 01, 2016 USD ($)	May 29, 2016 USD ($)	Dec. 03, 2010 USD ($)	Feb. 01, 2008 USD ($)	Feb. 01, 1998 USD ($)	Jan. 15, 1996 USD ($)
Debt Instrument [Line Items]
Unamortized debt issuance costs								$ 29	$ 38
Eurodollar
Debt Instrument [Line Items]
Interest rate margin	1.00%
1.999% notes, due April 27, 2018
Debt Instrument [Line Items]
Notes payable			$ 500
Interest rate on fixed rate debt (percent)			1.999%
Basis points in addition to treasury rate defined for redemption			20
2.7% notes, due April 27, 2020
Debt Instrument [Line Items]
Notes payable			$ 400
Interest rate on fixed rate debt (percent)			2.70%
Basis points in addition to treasury rate defined for redemption			20
3.832% notes, due April 27, 2025
Debt Instrument [Line Items]
Notes payable			$ 600
Interest rate on fixed rate debt (percent)			3.832%
Basis points in addition to treasury rate defined for redemption			30
4.854% notes, due April 27, 2035
Debt Instrument [Line Items]
Notes payable			$ 400
Interest rate on fixed rate debt (percent)			4.854%
Basis points in addition to treasury rate defined for redemption			35
5.054% notes, due April 27, 2045
Debt Instrument [Line Items]
Notes payable			$ 500
Interest rate on fixed rate debt (percent)			5.054%
Basis points in addition to treasury rate defined for redemption			40
4.25% notes, due October 1, 2016 (Exelis)
Debt Instrument [Line Items]
Notes payable		$ 250
Interest rate on fixed rate debt (percent)		4.25%
5.55% notes, due October 1, 2021
Debt Instrument [Line Items]
Notes payable		$ 400
Interest rate on fixed rate debt (percent)		5.55%
5.95% notes, due December 1, 2017
Debt Instrument [Line Items]
Notes payable					$ 400
Interest rate on fixed rate debt (percent)					5.95%
Make-whole redemption price					$ 448
5.95% notes, due December 1, 2017 \| Non-operating income (loss)
Debt Instrument [Line Items]
Loss on pre-payment of long term debt							$ 51
6.375% notes, due June 15, 2019
Debt Instrument [Line Items]
Notes payable				$ 350
Interest rate on fixed rate debt (percent)				6.375%
Make-whole redemption price				$ 415
6.375% notes, due June 15, 2019 \| Non-operating income (loss)
Debt Instrument [Line Items]
Loss on pre-payment of long term debt							$ 67
4.4% notes, due December 15, 2020
Debt Instrument [Line Items]
Notes payable											$ 400
Interest rate on fixed rate debt (percent)											4.40%
Offered repurchase price of notes in percentage of aggregate principal amount of notes											101.00%
Basis points in addition to treasury rate defined for redemption											25
Principal amount of notes for calculation of make-whole redemption price (as percent)											100.00%
Debt issuance costs and discounts											$ 6
6.15% notes, due December 15, 2040
Debt Instrument [Line Items]
Notes payable											$ 300
Interest rate on fixed rate debt (percent)											6.15%
Offered repurchase price of notes in percentage of aggregate principal amount of notes											101.00%
Basis points in addition to treasury rate defined for redemption											35
Principal amount of notes for calculation of make-whole redemption price (as percent)											100.00%
Debt issuance costs and discounts											$ 5
7.0% debentures, due January 15, 2026
Debt Instrument [Line Items]
Notes payable														$ 100
Interest rate on fixed rate debt (percent)														7.00%
6.35% debentures, due February 1, 2028
Debt Instrument [Line Items]
Notes payable													$ 150
Interest rate on fixed rate debt (percent)													6.35%
Repurchased and retire principal amount of debentures					$ 25
Redemption of debentures								26				$ 99
Fixed Rate Debt Securities
Debt Instrument [Line Items]
Notes payable			$ 2,400
New Notes
Debt Instrument [Line Items]
Debt issuance costs			$ 23
Debt covenant, customary event of default, failure to pay interest period		30 days
Debt covenant, customary event of default, failure to pay principal period		90 days
Percentage of number of trustee or holders to outstanding principal amount		25.00%
Debt instrument redemption price (as percent)		100.00%	100.00%
New Notes \| External Credit Rating, Investment Grade
Debt Instrument [Line Items]
Debt instrument redemption price (as percent)			101.00%
Exelis Notes
Debt Instrument [Line Items]
Unamortized debt issuance costs		$ 52
Exelis Notes \| Exelis
Debt Instrument [Line Items]
Fair value of long-term debt		$ 702
Repayments of long-term debt						$ 250
Variable Rate Term Loan Agreement
Debt Instrument [Line Items]
Debt issuance costs										$ 6
Repayments of long-term debt								$ 313
Variable Rate Term Loan Agreement \| Eurodollar
Debt Instrument [Line Items]
Interest rate margin		100.00%
Variable Rate Term Loan Agreement \| Treasury Rate
Debt Instrument [Line Items]
Interest rate margin		50.00%