Fair Value Measurements - Assets and Liabilities Measured on Recurring Basis Table (Details) - Recurring Fair Value Measurements [Member] - USD ($) $ in Millions		Jun. 30, 2016	Dec. 31, 2015
Assets
Cash and cash equivalents		$ 492	$ 836
Restricted cash and cash equivalents	[1]	33	33
Price risk management assets:
Foreign currency contracts assets	[2]	393	209
Cross-currency swaps assets	[2]	92	86
Total price risk management assets	[2]	485	295
Auction rate securities	[3]	2	2
Total assets		1,012	1,166
Price risk management liabilities:
Interest rate swaps liabilities	[2]	56	71
Foreign currency contracts liabilities	[2]	0	1
Total price risk management liabilities	[2]	56	72
Level 1 [Member]
Assets
Cash and cash equivalents		492	836
Restricted cash and cash equivalents	[1]	33	33
Price risk management assets:
Foreign currency contracts assets	[2]	0	0
Cross-currency swaps assets	[2]	0	0
Total price risk management assets	[2]	0	0
Auction rate securities	[3]	0	0
Total assets		525	869
Price risk management liabilities:
Interest rate swaps liabilities	[2]	0	0
Foreign currency contracts liabilities	[2]	0	0
Total price risk management liabilities	[2]	0	0
Level 2 [Member]
Assets
Cash and cash equivalents		0	0
Restricted cash and cash equivalents	[1]	0	0
Price risk management assets:
Foreign currency contracts assets	[2]	393	209
Cross-currency swaps assets	[2]	92	86
Total price risk management assets	[2]	485	295
Auction rate securities	[3]	0	0
Total assets		485	295
Price risk management liabilities:
Interest rate swaps liabilities	[2]	56	71
Foreign currency contracts liabilities	[2]	0	1
Total price risk management liabilities	[2]	56	72
Level 3 [Member]
Assets
Cash and cash equivalents		0	0
Restricted cash and cash equivalents	[1]	0	0
Price risk management assets:
Foreign currency contracts assets	[2]	0	0
Cross-currency swaps assets	[2]	0	0
Total price risk management assets	[2]	0	0
Auction rate securities	[3]	2	2
Total assets		2	2
Price risk management liabilities:
Interest rate swaps liabilities	[2]	0	0
Foreign currency contracts liabilities	[2]	0	0
Total price risk management liabilities	[2]	0	0
PPL Electric Utilities Corp [Member]
Assets
Cash and cash equivalents		35	47
Restricted cash and cash equivalents	[1]	2	2
Price risk management assets:
Total assets		37	49
PPL Electric Utilities Corp [Member] | Level 1 [Member]
Assets
Cash and cash equivalents		35	47
Restricted cash and cash equivalents	[1]	2	2
Price risk management assets:
Total assets		37	49
PPL Electric Utilities Corp [Member] | Level 2 [Member]
Assets
Cash and cash equivalents		0	0
Restricted cash and cash equivalents	[1]	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	[1]	0	0
Price risk management assets:
Total assets		0	0
LG And E And KU Energy LLC [Member]
Assets
Cash and cash equivalents		16	30
Price risk management assets:
Cash collateral posted to counterparties	[4]	9	9
Total assets		25	39
Price risk management liabilities:
Interest rate swaps liabilities		56	47
Total price risk management liabilities		56	47
LG And E And KU Energy LLC [Member] | Level 1 [Member]
Assets
Cash and cash equivalents		16	30
Price risk management assets:
Cash collateral posted to counterparties	[4]	9	9
Total assets		25	39
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	[4]	0	0
Total assets		0	0
Price risk management liabilities:
Interest rate swaps liabilities		56	47
Total price risk management liabilities		56	47
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	[4]	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		8	19
Price risk management assets:
Cash collateral posted to counterparties	[4]	9	9
Total assets		17	28
Price risk management liabilities:
Interest rate swaps liabilities		56	47
Total price risk management liabilities		56	47
Louisville Gas And Electric Co [Member] | Level 1 [Member]
Assets
Cash and cash equivalents		8	19
Price risk management assets:
Cash collateral posted to counterparties	[4]	9	9
Total assets		17	28
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	[4]	0	0
Total assets		0	0
Price risk management liabilities:
Interest rate swaps liabilities		56	47
Total price risk management liabilities		56	47
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	[4]	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		8	11
Price risk management assets:
Total assets		8	11
Kentucky Utilities Co [Member] | Level 1 [Member]
Assets
Cash and cash equivalents		8	11
Price risk management assets:
Total assets		8	11
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

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

[2] Current portion is included in "Price risk management assets" and "Other current liabilities" and noncurrent portion is included in "Price risk management 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. Represents cash collateral posted to offset the exposure with counterparties related to certain interest rate swaps under master netting arrangements that are not offset.