FINANCIAL INSTRUMENTS - Assets and Liabilities Not Carried at Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Carrying amount (net)
Assets
Loans and other receivables	$ 3,912	$ 4,113
Liabilities
Borrowings (Note 11)	85,154	90,882
Investment contracts (Note 12)	2,169	2,191
Estimated fair value
Assets
Loans and other receivables	3,777	4,208
Liabilities
Borrowings (Note 11)	85,033	97,754
Investment contracts (Note 12)	2,485	2,588
Accrued interest	$ 913	$ 1,106