PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Estimated Pretax Amortization of Net (Gain) Loss and Prior Service Credit (Details) $ in Millions	Dec. 31, 2017 USD ($)
Pension Plan [Member]
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year	$ 679
Prior service credit	(25)
Other Postretirement Benefits [Member]
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year	$ (24)

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (s)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant