New Accounting Guidance Pending Adoption New Accounting Guidance Pending Adoption (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Pension Plan [Member] \| U.K. [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated Impact Of Adoption Of ASU 2017-07	$ 175	$ 120

Estimated impact of the non-service cost components of net periodic benefit costs in a credit position to be reclassified from Other Operation and Maintenance to Other Income (Expense)- net as a result of adopting ASU 2017-07.

No definition available.

Name:	ppl_EstimatedImpactOfAdoptionOfASU201707
Namespace Prefix:	ppl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration