Fair Value Measurements and Credit Concentration (Net Asset and Liability Measured on Recurring Basis Level 3 Unobservable Inputs Reconciliation Rollforward) (Details) (Level 3 [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Reconciliation of net assets and liabilities
Balance at beginning of period	$ 39		$ 41
Total realized/unrealized gains (losses)
Included in earnings	(5)		1
Included in OCI	1	[1]	2	[1]
Sales	(2)		(5)
Settlements	(3)		(13)
Transfers into Level 3	16		8
Transfers out of Level 3	(3)		5
Balance at end of period	43		39
Energy Commodities, Net [Member]
Reconciliation of net assets and liabilities
Balance at beginning of period	22		13
Total realized/unrealized gains (losses)
Included in earnings	(5)		2
Included in OCI			1	[1]
Sales	(2)
Settlements	(3)		(13)
Transfers into Level 3	10		8
Transfers out of Level 3	2		11
Balance at end of period	24		22
Auction Rate Securities [Member]
Reconciliation of net assets and liabilities
Balance at beginning of period	16		24
Total realized/unrealized gains (losses)
Included in earnings
Included in OCI
Sales			(5)
Settlements
Transfers into Level 3	3
Transfers out of Level 3			(3)
Balance at end of period	19		16
Cross Currency Swaps [Member]
Reconciliation of net assets and liabilities
Balance at beginning of period	1		4
Total realized/unrealized gains (losses)
Included in earnings			(1)
Included in OCI	1	[1]	1	[1]
Sales
Settlements
Transfers into Level 3	3
Transfers out of Level 3	(5)		(3)
Balance at end of period			1
PPL Energy Supply LLC [Member]
Reconciliation of net assets and liabilities
Balance at beginning of period	35		32
Total realized/unrealized gains (losses)
Included in earnings	(5)		2
Included in OCI			1	[2]
Sales	(2)		(3)
Settlements	(3)		(13)
Transfers into Level 3	13		8
Transfers out of Level 3	2		8
Balance at end of period	40		35
PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member]
Reconciliation of net assets and liabilities
Balance at beginning of period	22		13
Total realized/unrealized gains (losses)
Included in earnings	(5)		2
Included in OCI			1	[2]
Sales	(2)
Settlements	(3)		(13)
Transfers into Level 3	10		8
Transfers out of Level 3	2		11
Balance at end of period	24		22
PPL Energy Supply LLC [Member] | Auction Rate Securities [Member]
Reconciliation of net assets and liabilities
Balance at beginning of period	13		19
Total realized/unrealized gains (losses)
Included in earnings
Included in OCI
Sales			(3)
Settlements
Transfers into Level 3	3
Transfers out of Level 3			(3)
Balance at end of period	$ 16		$ 13

[1] "Energy Commodities" and "Cross-Currency Swaps" are included in "Qualifying derivatives" and "Auction Rate Securities" are included in "Available-for-sale securities" on the Statements of Comprehensive Income.

[2] "Energy Commodities" are included in "Qualifying derivatives" and "Auction Rate Securities" are included in "Available-for-sale securities" on the Statements of Comprehensive Income.