Fair Value Measurements (Financial Instruments Not Recorded at Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Carrying Amount [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	$ 18,326	$ 19,048
Fair Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	21,355	21,218
PPL Electric Utilities Corp [Member] | Carrying Amount [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	2,831	2,828
PPL Electric Utilities Corp [Member] | Fair Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	3,148	3,088
LG And E And KU Energy LLC [Member] | Carrying Amount [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	5,065	5,088
LG And E And KU Energy LLC [Member] | Fair Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	5,439	5,384
Louisville Gas And Electric Co [Member] | Carrying Amount [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	1,617	1,642
Louisville Gas And Electric Co [Member] | Fair Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	1,710	1,704
Kentucky Utilities Co [Member] | Carrying Amount [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	2,327	2,326
Kentucky Utilities Co [Member] | Fair Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	$ 2,514	$ 2,467