EMPLOYEE BENEFIT PLANS (Reconciliation of Changes in Plan Assets Benefit Obligations and Funded Status) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Funded Status:
Noncurrent liability	$ (860)	$ (2,444)
Pension Plan
Change in plan assets:
Fair value of plan assets at beginning of year	20,759	18,547
Actual return on plan assets	1,693	2,736
Company contributions	335	343
Benefits and expenses paid	(892)	(867)
Fair value of plan assets at end of year	21,895	20,759	$ 18,547
Change in benefit obligation:
Benefit obligation at beginning of year	23,172	20,525
Service cost for benefits earned	587	530	443
Interest cost	645	713	758
Actuarial (gain) loss	(752)	2,271
Plan amendments	0	0
Benefits and expenses paid	(893)	(867)
Benefit obligation at end of year	22,759	23,172	20,525
Funded Status:
Current liability	(9)	(3)
Noncurrent liability	(856)	(2,410)
Net (liability) asset at end of year	(865)	(2,413)
Accumulated benefit obligation	20,400	20,700
PBOP Plans
Change in plan assets:
Fair value of plan assets at beginning of year	2,995	2,678
Actual return on plan assets	193	379
Company contributions	10	26
Plan participant contribution	80	81
Benefits and expenses paid	(176)	(169)
Fair value of plan assets at end of year	3,102	2,995	2,678
Change in benefit obligation:
Benefit obligation at beginning of year	1,876	1,832
Service cost for benefits earned	63	61	56
Interest cost	51	63	76
Actuarial (gain) loss	(152)	(14)
Benefits and expenses paid	(156)	(149)
Federal subsidy on benefits paid	4	3
Plan participant contributions	80	80
Benefit obligation at end of year	1,766	1,876	$ 1,832
Funded Status:
Noncurrent asset	1,340	1,153
Noncurrent liability	(4)	(34)
Net (liability) asset at end of year	1,336	1,119
PBOP Plans | Postretirement Life Insurance Plan
Change in plan assets:
Fair value of plan assets at beginning of year	343
Fair value of plan assets at end of year	359	343
Change in benefit obligation:
Benefit obligation at beginning of year	377
Benefit obligation at end of year	$ 363	$ 377