FAIR VALUE MEASUREMENT OF ASSETS AND LIABILITIES - Summary of Investments Under the Fair Value Option (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2022 |
Sep. 30, 2021 |
Sep. 30, 2022 |
Sep. 30, 2021 |
Dec. 31, 2021 |
|
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |||||
| Debt securities, available-for-sale, excluding accrued interest | $ 24,767 | $ 24,767 | $ 23,145 | ||
| Fair Value Option, Investments | Funds receivable and customer accounts | |||||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |||||
| Debt securities, available-for-sale, excluding accrued interest | 847 | 847 | 2,327 | ||
| Net gains (losses) from fair value changes | (70) | $ (45) | (213) | $ (85) | |
| Fair Value Option, Investments | Short-term investments | |||||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |||||
| Debt securities, available-for-sale, excluding accrued interest | 0 | 0 | $ 13 | ||
| Net gains (losses) from fair value changes | $ 0 | $ (18) | $ 0 | $ (25) | |