EMPLOYEE BENEFITS (Details - Changes in Level 3 fair value measurements) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Changes in Level 3 fair value measurements
Purchases	$ 4,053	$ 5,974
Sales	(1,071)	(971)
Settlements	(7,629)	(6,278)
Issuances	0	0
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	487	(410)
Pensions \| U.S. Plans
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	3,843	4,359
Net Realized and Unrealized Gains (Losses)	584	154
Fair value of plan assets, end of year	4,350	3,843
Pensions \| U.S. Plans \| Level 3
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	26	37
Net Realized and Unrealized Gains (Losses)	(3)	(3)
Purchases	18	6
Sales	(14)	(14)
Settlements	0	0
Issuances	0	0
Transfers In	0	0
Transfers Out	0	0
Fair value of plan assets, end of year	27	26
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	1	(4)
Pensions \| U.S. Plans \| Level 3 \| Fixed maturity securities: U.S. investment grade
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	2	9
Net Realized and Unrealized Gains (Losses)	0	1
Purchases	17	2
Sales	(7)	(10)
Settlements	0	0
Issuances	0	0
Transfers In	0	0
Transfers Out	0	0
Fair value of plan assets, end of year	12	2
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	2	0
Pensions \| U.S. Plans \| Level 3 \| Direct private equity
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	24	28
Net Realized and Unrealized Gains (Losses)	(3)	(4)
Purchases	1	4
Sales	(7)	(4)
Settlements	0	0
Issuances	0	0
Transfers In	0	0
Transfers Out	0	0
Fair value of plan assets, end of year	15	24
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	(1)	(4)
Pensions \| U.S. Plans \| Level 3 \| Hedge funds
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Pensions \| U.S. Plans \| Level 3 \| Mortgage-backed, asset-backed and collateralized
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Pensions \| U.S. Plans \| Level 3 \| Insurance contracts
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Pensions \| Non U.S. Plans
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	803	773
Net Realized and Unrealized Gains (Losses)	67	19
Fair value of plan assets, end of year	875	803
Pensions \| Non U.S. Plans \| Level 3
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	108	95
Net Realized and Unrealized Gains (Losses)	4	12
Purchases	1	1
Sales	0	0
Settlements	0	0
Issuances	0	0
Transfers In	0	2
Transfers Out	0	(2)
Fair value of plan assets, end of year	113	108
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Pensions \| Non U.S. Plans \| Level 3 \| Direct private equity
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Pensions \| Non U.S. Plans \| Level 3 \| Hedge funds
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Pensions \| Non U.S. Plans \| Level 3 \| Mortgage-backed, asset-backed and collateralized
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Pensions \| Non U.S. Plans \| Level 3 \| Other fixed maturity securities
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	0	0
Net Realized and Unrealized Gains (Losses)	0	0
Purchases	0	0
Sales	0	0
Settlements	0	0
Issuances	0	0
Transfers In	0	0
Transfers Out	0	0
Fair value of plan assets, end of year	0	0
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Pensions \| Non U.S. Plans \| Level 3 \| Insurance contracts
Changes in Level 3 fair value measurements
Fair value of plan assets, beginning of year	108	95
Net Realized and Unrealized Gains (Losses)	4	12
Purchases	1	1
Sales	0	0
Settlements	0	0
Issuances	0	0
Transfers In	0	2
Transfers Out	0	(2)
Fair value of plan assets, end of year	113	108
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	$ 0	$ 0

Transfers in to Level 3. For example, transfers due to changes in the observability of significant inputs.

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- Definition

Transfers out of Level 3. For example, transfers due to changes in the observability of significant inputs.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

+ 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 (b)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ 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 (b)
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- Definition

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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