ACCOUNTS RECEIVABLE - Other Receivables (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accounts receivable and allowance for doubtful accounts
Receivables	$ 2,595	$ 2,616
Payables	1,207	1,175
California's Provider Fee Program \| Other current assets
Accounts receivable and allowance for doubtful accounts
Receivables	278	312
California's Provider Fee Program \| Investments and other assets
Accounts receivable and allowance for doubtful accounts
Receivables	231	266
California's Provider Fee Program \| Other current liabilities
Accounts receivable and allowance for doubtful accounts
Payables	100	159
California's Provider Fee Program \| Other long-term liabilities
Accounts receivable and allowance for doubtful accounts
Payables	$ 42	$ 49

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a))
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

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-Topic 210
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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