CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	$ 51	$ 54
Equity
Common stock par value	$ 0.01	$ 0.01
Common stock shares authorized	1,560,000	1,560,000
Common stock shares issued	693,398	679,731
Common stock shares outstanding	693,398	679,731
PPL Electric Utilities Corp [Member]
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	$ 24	$ 28
Equity
Common stock no par value	$ 0.00	$ 0.00
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	$ 25	$ 24
Louisville Gas And Electric Co [Member]
Receivables Net Current [Abstract]
Accounts receivable reserve for uncollectible accounts	$ 1	$ 2
Equity
Common stock no par value	$ 0.00	$ 0.00
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	$ 1	$ 2
Equity
Common stock no par value	$ 0.00	$ 0.00
Common stock shares authorized	80,000	80,000
Common stock shares issued	37,818	37,818
Common stock shares outstanding	37,818	37,818