Retirement and Postemployment Benefits (Savings Plans and Employee Stock Ownership Plan) (Details) - Deferred Savings Plans 401K [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Contribution Pension And Other Postretirement Plans [Line Items]
Employer contributions to deferred savings plans	$ 34	$ 33	$ 29
PPL Electric Utilities Corp [Member]
Defined Contribution Pension And Other Postretirement Plans [Line Items]
Employer contributions to deferred savings plans	6	6	6
LG And E And KU Energy LLC [Member]
Defined Contribution Pension And Other Postretirement Plans [Line Items]
Employer contributions to deferred savings plans	16	15	13
Louisville Gas And Electric Co [Member]
Defined Contribution Pension And Other Postretirement Plans [Line Items]
Employer contributions to deferred savings plans	5	5	7
Kentucky Utilities Co [Member]
Defined Contribution Pension And Other Postretirement Plans [Line Items]
Employer contributions to deferred savings plans	$ 4	$ 4	$ 6