CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	$ 64	$ 54
Property, Plant and Equipment
PP&E, net from the consolidation of a VIE	428	416
Other Noncurrent Assets
Other intangibles from the consolidation of a VIE	10	11
Equity
Common stock par value	$ 0.01	$ 0.01
Common stock shares authorized	780,000	780,000
Common stock shares issued	581,944	578,405
Common stock shares outstanding	581,944	578,405
PPL Energy Supply LLC [Member]
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	23	15
Property, Plant and Equipment
PP&E, net from the consolidation of a VIE	428	416
Other Noncurrent Assets
Other intangibles from the consolidation of a VIE	10	11
PPL Electric Utilities Corp [Member]
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	18	17
Equity
Common stock no par value	no par value	no par value
Common stock shares authorized	170,000	170,000
Common stock shares issued	66,368	66,368
Common stock shares outstanding	66,368	66,368
LG And E And KU Energy LLC [Member]
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	19	17
Louisville Gas And Electric Co [Member]
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	1	2
Equity
Common stock no par value	no par value	no par value
Common stock shares authorized	75,000	75,000
Common stock shares issued	21,294	21,294
Common stock shares outstanding	21,294	21,294
Kentucky Utilities Co [Member]
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	$ 2	$ 2
Equity
Common stock no par value	no par value	no par value
Common stock shares authorized	80,000	80,000
Common stock shares issued	37,818	37,818
Common stock shares outstanding	37,818	37,818