POSTRETIREMENT BENEFITS AND EMPLOYEE STOCK OWNERSHIP PLAN - TOTAL BENEFIT PAYMENTS EXPECTED TO BE PAID (Details) $ in Millions	Jun. 30, 2017 USD ($)
Pension Plan
EXPECTED BENEFIT PAYMENTS
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	$ 524
Defined Benefit Plan, Expected Future Benefit Payments, Year Two	530
Defined Benefit Plan, Expected Future Benefit Payments, Year Three	539
Defined Benefit Plan, Expected Future Benefit Payments, Year Four	575
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	596
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter	3,221
Other Retiree Benefits
EXPECTED BENEFIT PAYMENTS
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	198
Defined Benefit Plan, Expected Future Benefit Payments, Year Two	211
Defined Benefit Plan, Expected Future Benefit Payments, Year Three	222
Defined Benefit Plan, Expected Future Benefit Payments, Year Four	232
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	242
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter	$ 1,334

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next 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.

+ References

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- Definition

Amount of benefits from a defined benefit plan expected to be paid 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 benefits from a defined benefit plan expected to be paid in the fourth 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 benefits from a defined benefit plan expected to be paid 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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Amount of benefits from a defined benefit plan expected to be paid in the second 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.

+ References

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