CONSOLIDATED DEBT Equipment Financing Capital Lease (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Maximum [Member]
Capital Leased Assets [Line Items]
Debt Instrument, Term	12 years
Minimum [Member]
Capital Leased Assets [Line Items]
Debt Instrument, Term	10 years
Junior Loans [Member] \| Maximum [Member]
Capital Leased Assets [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.52%
Junior Loans [Member] \| Minimum [Member]
Capital Leased Assets [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.48%
3.63% - 4.25% Equipment Financing Capital Lease [Member]
Capital Leased Assets [Line Items]
Capital Lease Obligations	$ 69	$ 69
Capital Leases, Future Minimum Payments Receivable, Next Twelve Months	5
Capital Leases, Future Minimum Payments Due in Two Years	6
Capital Leases, Future Minimum Payments Due in Three Years	6
Capital Leases, Future Minimum Payments Due in Four Years	6
Capital Leases, Future Minimum Payments Due in Five Years	6
Capital Leases, Future Minimum Payments Due Thereafter	$ 40
3.63% - 4.25% Equipment Financing Capital Lease [Member] \| Maximum [Member]
Capital Leased Assets [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.61%
3.63% - 4.25% Equipment Financing Capital Lease [Member] \| Minimum [Member]
Capital Leased Assets [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.48%

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738

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Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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