SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Jul. 01, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jul. 01, 2018	Jun. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting changes, net of tax	$ 695	$ 555		$ 559	$ 781	$ 742		$ 726
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting changes, net of tax	$ 3,398	$ 3,292		$ 3,150	$ 3,004	$ 2,940		$ 2,797
Cumulative Effect of Accounting Changes, Net of Tax [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting changes, net of tax			$ 22				$ (3)
Cumulative Effect of Accounting Changes, Net of Tax [Member] | Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of accounting changes, net of tax			$ 22				$ (3)