Fair Value Measurements and Credit Concentration (Assets and Liabilities Measured on Recurring Basis Table) (Details) - Recurring [Member] - USD ($) $ in Millions		Jun. 30, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents		$ 846	$ 1,399
Short-term investments		0	120
Restricted cash and cash equivalents	[1]	32	31
Price risk management assets:
Foreign currency contracts assets	[2]	93	130
Cross-currency swaps assets	[2]	63	29
Total price risk management assets	[2]	156	159
Auction rate securities	[3]	2	2
Total assets		1,036	1,711
Price risk management liabilities:
Interest rate swaps liabilities	[2]	104	156
Foreign currency contracts liabilities	[2]	20	2
Cross-currency swaps liabilities		0	3	[2]
Total price risk management liabilities	[2]	124	161
Level 1 [Member]
Assets
Cash and cash equivalents		846	1,399
Short-term investments		0	120
Restricted cash and cash equivalents	[1]	32	31
Price risk management assets:
Foreign currency contracts assets		0	0
Cross-currency swaps assets		0	0
Total price risk management assets		0	0
Auction rate securities		0	0
Total assets		878	1,550
Price risk management liabilities:
Interest rate swaps liabilities		0	0
Foreign currency contracts liabilities		0	0
Cross-currency swaps liabilities		0	0
Total price risk management liabilities		0	0
Level 2 [Member]
Assets
Cash and cash equivalents		0	0
Short-term investments		0	0
Restricted cash and cash equivalents		0	0
Price risk management assets:
Foreign currency contracts assets	[2]	93	130
Cross-currency swaps assets	[2]	63	28
Total price risk management assets	[2]	156	158
Auction rate securities		0	0
Total assets		156	158
Price risk management liabilities:
Interest rate swaps liabilities	[2]	104	156
Foreign currency contracts liabilities	[2]	20	2
Cross-currency swaps liabilities		0	3	[2]
Total price risk management liabilities	[2]	124	161
Level 3 [Member]
Assets
Cash and cash equivalents		0	0
Short-term investments		0	0
Restricted cash and cash equivalents		0	0
Price risk management assets:
Foreign currency contracts assets		0	0
Cross-currency swaps assets		0	1	[2]
Total price risk management assets		0	1	[2]
Auction rate securities	[3]	2	2
Total assets		2	3
Price risk management liabilities:
Interest rate swaps liabilities		0	0
Foreign currency contracts liabilities		0	0
Cross-currency swaps liabilities		0	0
Total price risk management liabilities		0	0
PPL Electric Utilities Corp [Member]
Assets
Cash and cash equivalents		28	214
Restricted cash and cash equivalents	[1]	2	3
Price risk management assets:
Total assets		30	217
PPL Electric Utilities Corp [Member] | Level 1 [Member]
Assets
Cash and cash equivalents		28	214
Restricted cash and cash equivalents	[1]	2	3
Price risk management assets:
Total assets		30	217
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		13	21
Price risk management assets:
Cash collateral posted to counterparties	[4]	9	21
Total assets		22	42
Price risk management liabilities:
Interest rate swaps liabilities		91	114
Total price risk management liabilities		91	114
LG And E And KU Energy LLC [Member] | Level 1 [Member]
Assets
Cash and cash equivalents		13	21
Price risk management assets:
Cash collateral posted to counterparties	[4]	9	21
Total assets		22	42
Price risk management liabilities:
Interest rate swaps liabilities		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:
Cash collateral posted to counterparties		0	0
Total assets		0	0
Price risk management liabilities:
Interest rate swaps liabilities		91	114
Total price risk management liabilities		91	114
LG And E And KU Energy LLC [Member] | Level 3 [Member]
Assets
Cash and cash equivalents		0	0
Price risk management assets:
Cash collateral posted to counterparties		0	0
Total assets		0	0
Price risk management liabilities:
Interest rate swaps liabilities		0	0
Total price risk management liabilities		0	0
Louisville Gas And Electric Co [Member]
Assets
Cash and cash equivalents		7	10
Price risk management assets:
Cash collateral posted to counterparties	[4]	9	21
Total assets		16	31
Price risk management liabilities:
Interest rate swaps liabilities		68	81
Total price risk management liabilities		68	81
Louisville Gas And Electric Co [Member] | Level 1 [Member]
Assets
Cash and cash equivalents		7	10
Price risk management assets:
Cash collateral posted to counterparties	[4]	9	21
Total assets		16	31
Price risk management liabilities:
Interest rate swaps liabilities		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:
Cash collateral posted to counterparties		0	0
Total assets		0	0
Price risk management liabilities:
Interest rate swaps liabilities		68	81
Total price risk management liabilities		68	81
Louisville Gas And Electric Co [Member] | Level 3 [Member]
Assets
Cash and cash equivalents		0	0
Price risk management assets:
Cash collateral posted to counterparties		0	0
Total assets		0	0
Price risk management liabilities:
Interest rate swaps liabilities		0	0
Total price risk management liabilities		0	0
Kentucky Utilities Co [Member]
Assets
Cash and cash equivalents		6	11
Price risk management assets:
Total assets		6	11
Price risk management liabilities:
Interest rate swaps liabilities		23	33
Total price risk management liabilities		23	33
Kentucky Utilities Co [Member] | Level 1 [Member]
Assets
Cash and cash equivalents		6	11
Price risk management assets:
Total assets		6	11
Price risk management liabilities:
Interest rate swaps liabilities		0	0
Total price risk management liabilities		0	0
Kentucky Utilities 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 liabilities		23	33
Total price risk management liabilities		23	33
Kentucky Utilities 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 liabilities		0	0
Total price risk management liabilities		$ 0	$ 0

[1] Current portion is included in "Other current assets" and long-term portion is included in "Other noncurrent assets" on the Balance Sheets.

[2] Included in “Other current assets”, “Other current liabilities”, “Other noncurrent assets” and “Other deferred credits and noncurrent liabilities” on the Balance Sheets.

[3] Included in "Other noncurrent assets" on the Balance Sheets.

[4] Included in "Other noncurrent assets" on the Balance Sheets. R epresent s cash collateral posted to offset the exposure with co unterparties related to certain interest rate swaps under master netting arrangements that are not offset.