SHARE-BASED COMPENSATION PLANS (Details - Share based compensation expense) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SHARE-BASED COMPENSATION PLANS
Share-based compensation expense - pre-tax	$ 274	$ 314	$ 337
Share-based compensation expense - after tax	216	248	266
Vested stock-settled awards issued to retirement eligible employees	63	$ 82	$ 104
Excess tax benefits due to share settlements	$ 25

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount, after tax, of expense for award under share-based payment arrangement.

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No definition available.

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Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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