Defined Benefits (Details) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Health Care Reform (Numeric)
Decrease in deferred tax assets as a result of the Health Care Reform				$ 13
Increase in regulatory assets as a result of the Health Care Reform				9
Increase in deferred tax liability as a result of the Health Care Reform				4
Effect of Health Care Reform on income tax expense	0	0	0	8
Pension Benefits - U.S. [Member]
Net Periodic Defined Benefit Costs (Credits)
Service cost	23	15	47	30
Interest cost	54	37	109	74
Expected return on plan assets	(61)	(44)	(123)	(88)
Amortization of:
Prior service cost	6	5	12	10
Actuarial (gain) loss	8	1	14	2
Net periodic defined benefit costs (credits) prior to termination benefits	30	14	59	28
Termination benefits	0	0	0	0
Net periodic defined benefit costs (credits)	30	14	59	28
Pension Benefits - U.K. [Member]
Net Periodic Defined Benefit Costs (Credits)
Service cost	12	4	17	9
Interest cost	73	36	112	75
Expected return on plan assets	(88)	(49)	(140)	(99)
Amortization of:
Prior service cost	1	1	2	2
Actuarial (gain) loss	15	12	29	24
Net periodic defined benefit costs (credits) prior to termination benefits	13	4	20	11
Termination benefits	2	0	2	0
Net periodic defined benefit costs (credits)	15	4	22	11
Expected contribution to pension plans	111		111		15
Cash contributions to the pension plan			91
Contributions required to fund the acquired WPD Midlands' plan			27
PPL WW contributions to prepay future contribution requirements to fund pension plan deficits			69
Other Postretirement Benefits - U.S. [Member]
Net Periodic Defined Benefit Costs (Credits)
Service cost	3	2	6	4
Interest cost	8	7	16	14
Expected return on plan assets	(5)	(5)	(11)	(10)
Amortization of:
Transition obligation	1	2	1	4
Prior service cost	0	2	0	4
Actuarial (gain) loss	1	1	3	2
Net periodic defined benefit costs (credits)	$ 8	$ 9	$ 15	$ 18