ACCOUNTS RECEIVABLE AND ALLOWANCE FOR DOUBTFUL ACCOUNTS - Components (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Accounts receivable and allowance for doubtful accounts
Accounts receivable, net	$ 2,786	$ 2,704
Continuing operations
Accounts receivable and allowance for doubtful accounts
Patient accounts receivable	3,666	3,486
Allowance for doubtful accounts	(981)	(887)
Estimated future recoveries	141	144
Net cost reports and settlements payable and valuation allowances	(42)	(42)
Accounts receivable, net	2,784	2,701
Discontinued operations
Accounts receivable and allowance for doubtful accounts
Accounts receivable, net	$ 2	$ 3