Fair Value Measurements (Assets and Liabilities Measured on Recurring Basis Table) (Details) - Recurring [Member] - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 815	$ 621
Restricted cash and cash equivalents	21	22
Money market fund	0	59
Commingled debt fund measured at NAV	29	0
Commingled equity fund measured at NAV	27	0
Total special use funds	56	59
Price risk management assets:
Foreign currency contracts	142	202
Cross-currency swaps	154	135
Total price risk management assets	296	337
Total Assets	1,188	1,039
Price risk management liabilities:
Interest rate swaps	21	20
Foreign currency contracts	5	2
Total price risk management liabilities	26	22
Level 1 [Member]
Assets
Cash and cash equivalents	815	621
Restricted cash and cash equivalents	21	22
Money market fund	0	59
Total special use funds	0	59
Price risk management assets:
Foreign currency contracts	0	0
Cross-currency swaps	0	0
Total price risk management assets	0	0
Total Assets	836	702
Price risk management liabilities:
Interest rate swaps	0	0
Foreign currency contracts	0	0
Total price risk management liabilities	0	0
Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Restricted cash and cash equivalents	0	0
Money market fund	0	0
Total special use funds	0	0
Price risk management assets:
Foreign currency contracts	142	202
Cross-currency swaps	154	135
Total price risk management assets	296	337
Total Assets	296	337
Price risk management liabilities:
Interest rate swaps	21	20
Foreign currency contracts	5	2
Total price risk management liabilities	26	22
Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Restricted cash and cash equivalents	0	0
Money market fund	0	0
Total special use funds	0	0
Price risk management assets:
Foreign currency contracts	0	0
Cross-currency swaps	0	0
Total price risk management assets	0	0
Total Assets	0	0
Price risk management liabilities:
Interest rate swaps	0	0
Foreign currency contracts	0	0
Total price risk management liabilities	0	0
PPL Electric Utilities Corp [Member]
Assets
Cash and cash equivalents	262	267
Restricted cash and cash equivalents	2	2
Price risk management assets:
Total Assets	264	269
PPL Electric Utilities Corp [Member] | Level 1 [Member]
Assets
Cash and cash equivalents	262	267
Restricted cash and cash equivalents	2	2
Price risk management assets:
Total Assets	264	269
PPL Electric Utilities Corp [Member] | Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Restricted cash and cash equivalents	0	0
Price risk management assets:
Total Assets	0	0
PPL Electric Utilities Corp [Member] | Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Restricted cash and cash equivalents	0	0
Price risk management assets:
Total Assets	0	0
LG And E And KU Energy LLC [Member]
Assets
Cash and cash equivalents	27	24
Price risk management assets:
Total Assets	27	24
Price risk management liabilities:
Interest rate swaps	21	20
Total price risk management liabilities	21	20
LG And E And KU Energy LLC [Member] | Level 1 [Member]
Assets
Cash and cash equivalents	27	24
Price risk management assets:
Total Assets	27	24
Price risk management liabilities:
Interest rate swaps	0	0
Total price risk management liabilities	0	0
LG And E And KU Energy LLC [Member] | Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total Assets	0	0
Price risk management liabilities:
Interest rate swaps	21	20
Total price risk management liabilities	21	20
LG And E And KU Energy LLC [Member] | Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total Assets	0	0
Price risk management liabilities:
Interest rate swaps	0	0
Total price risk management liabilities	0	0
Louisville Gas And Electric Co [Member]
Assets
Cash and cash equivalents	15	10
Price risk management assets:
Total Assets	15	10
Price risk management liabilities:
Interest rate swaps	21	20
Total price risk management liabilities	21	20
Louisville Gas And Electric Co [Member] | Level 1 [Member]
Assets
Cash and cash equivalents	15	10
Price risk management assets:
Total Assets	15	10
Price risk management liabilities:
Interest rate swaps	0	0
Total price risk management liabilities	0	0
Louisville Gas And Electric Co [Member] | Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total Assets	0	0
Price risk management liabilities:
Interest rate swaps	21	20
Total price risk management liabilities	21	20
Louisville Gas And Electric Co [Member] | Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total Assets	0	0
Price risk management liabilities:
Interest rate swaps	0	0
Total price risk management liabilities	0	0
Kentucky Utilities Co [Member]
Assets
Cash and cash equivalents	12	14
Price risk management assets:
Total Assets	12	14
Kentucky Utilities Co [Member] | Level 1 [Member]
Assets
Cash and cash equivalents	12	14
Price risk management assets:
Total Assets	12	14
Kentucky Utilities Co [Member] | Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total Assets	0	0
Kentucky Utilities Co [Member] | Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total Assets	$ 0	$ 0