NOTES PAYABLE AND DEBT - Annual principal payments (Details) $ in Millions	Dec. 31, 2020 USD ($)
Debt Disclosure [Abstract]
2021	$ 49
2022	615
2023	3
2024	3
2025	1,302
After 2025	1,726
Total payments	3,698
Add: unamortized premiums, net of discount	89
Total	$ 3,787

Total debt principal payments less unamortized discounts in the aggregate at the reporting date.

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Amount, after accumulated amortization, of debt discount.

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