ACCOUNTS RECEIVABLE - Components (Details) - USD ($) $ in Millions |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Accounts receivable and allowance for doubtful accounts | ||
| Accounts receivable | $ 2,519 | $ 2,616 |
| Continuing operations | ||
| Accounts receivable and allowance for doubtful accounts | ||
| Patient accounts receivable | 2,400 | 3,376 |
| Allowance for doubtful accounts | 0 | (898) |
| Estimated future recoveries | 127 | 132 |
| Net cost reports and settlements payable and valuation allowances | (10) | 4 |
| Accounts receivable | 2,517 | 2,614 |
| Discontinued operations | ||
| Accounts receivable and allowance for doubtful accounts | ||
| Accounts receivable | $ 2 | $ 2 |