PENSION AND OTHER POSTRETIREMENT BENEFITS - Reconciliation of Defined Benefit Plan Asset Balances (Details) - USD ($) $ in Millions	Jan. 03, 2020	Jun. 28, 2019	Jun. 29, 2018
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 8,892	$ 5,159	$ 5,305
Receivables, net	5	84	(4)
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,514	2,081	2,094
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,453	1,285	1,374
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	19	19	13
Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,986	3,385	3,481
Investments Measured at NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,901	1,690	1,828
Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,968	1,173	1,221
Domestic equities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,968	1,173	1,189
Domestic equities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	32
Domestic equities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
International equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,217	896	903
International equities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,217	896	899
International equities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	4
International equities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
Real Estate Investment Trusts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	211
Real Estate Investment Trusts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	211
Real Estate Investment Trusts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Real Estate Investment Trusts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,176	923	811
Corporate bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
Corporate bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,159	906	800
Corporate bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17	17	11
Government securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	489	332	335
Government securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
Government securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	489	332	335
Government securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
Securitized Assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	131
Securitized Assets | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Securitized Assets | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	131
Securitized Assets | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Fixed income investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	101
Fixed income investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	101
Fixed income investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Fixed income investments | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
Fixed income investments | Investments Measured at NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	323	362	318
Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	2	2
Other | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
Other | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
Other | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	2	2
Other | Investments Measured at NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	691	59	209
Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17	12	6
Cash and cash equivalents | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	674	47	203
Cash and cash equivalents | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0	0
Equity funds | Investments Measured at NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	933	703	714
Private equity funds | Investments Measured at NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	302	294	401
Hedge funds | Investments Measured at NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 342	$ 331	$ 395