FAIR VALUE MEASUREMENTS (Details - Difference between fair values and the aggregate contractual principal amounts of mortgage and other loans receivable and long-term borrowings for which the fair value option was elected) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage and other loans receivable, Fair Value	$ 0	$ 5
Mortgage and other loans receivable, Outstanding Principal Amount	40,334	37,345
Mortgage and other loans receivable, Difference	40,334	37,345
Long-term debt, Fair Value	2,615	2,888
Long-term debt, Outstanding Principal Amount	33,784	31,640
Fair Value Option
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage and other loans receivable, Fair Value	0	5
Mortgage and other loans receivable, Outstanding Principal Amount	0	5
Mortgage and other loans receivable, Difference	0	0
Long-term debt, Fair Value	2,615	2,888
Long-term debt, Outstanding Principal Amount	2,114	2,280
Long-term debt, Difference	$ 501	$ 608