LEASES - Supplemental Cash Flow Information (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Cash Paid For Amounts Included In The Measurement Of Lease Liabilities [Abstract]
Operating cash outflows from operating leases	$ 47
Operating cash outflows from finance leases	5
Financing cash outflows from finance leases	36
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	28
Finance leases	$ 36

Cash Paid For Amounts Included In The Measurement Of Lease Liabilities [Abstract]

No definition available.

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- Definition

Amount of interest paid on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(1)
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-Section 45
-Paragraph 5
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+ Details

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- Definition

Amount of cash outflow for principal payment on finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977

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- References

No definition available.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977

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- Definition

Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

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