Acquisitions, Development and Divestures (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				3 Months Ended	12 Months Ended	3 Months Ended	1 Months Ended	3 Months Ended
	Mar. 31, 2012 MW	Mar. 31, 2012 Proposed Natural Gas Fired Combined Cycle Turbine [Member] MW Integer	Mar. 31, 2012 Proposed Bell Bend Nuclear Unit [Member]	Dec. 31, 2011 Proposed Bell Bend Nuclear Unit [Member]	Mar. 31, 2012 UK Regulated [Member] One Time Termination Benefits [Member] Integer	Dec. 31, 2011 UK Regulated [Member] One Time Termination Benefits [Member]	Mar. 31, 2012 UK Regulated [Member] Severance Compensation [Member]	Apr. 30, 2012 Ironwood [Member]	Mar. 31, 2011 WPD Midlands [Member]	Mar. 31, 2011 WPD Midlands [Member] Interest Expense [Member]	Mar. 31, 2011 WPD Midlands [Member] Other Income Expense Net [Member]	Mar. 31, 2012 Pending Bluegrass Plant Acquistion [Member] MW
Business Acquisition [Line Items]
Acquisition date								April 2012	2011
Future minimum lease payments that will no longer be payable after acquisition								$ 270
Interest rate of debt assumed								8.857%
Maturity date (in year)								Dec. 31, 2025
Debt outstanding								226
Debt service reserve loans expected to assume								8
Restricted cash reserves expected to acquire								17
Capacity of purchased units (in MW)												495
Purchase price												110
LG&E ownership percentage												69.00%
KU ownership percentage												31.00%
Fair Value of Consideration Paid for Acquisition [Abstract]
Aggregate enterprise consideration								302
Less: estimated long-term debt outstanding assumed through consolidation (net of restricted cash reserves)								217
Cash consideration paid for equity interests (including estimated working capital adjustments)								85
Business Acquisition, Pro Forma Information [Abstract]
Operating Revenues - PPL consolidated pro forma									3,215
Net Income (Loss) Attributable to PPL - PPL consolidated pro forma									526
2011 Bridge Facility costs										(7)
Net hedge losses											(7)
Other acquisition-related costs											(11)
Separation Benefits - U.K. Regulated Segment
Number of employees impacted					700
Expected costs to be incurred					104
Accrued severance at beginning of period							21
Severance compensation						93	6
Severance paid							(8)
Accrued severance at end of period							19
Development Projects [Abstract]
Completed capacity expansion (in MW)		640
Expected capital cost of an expansion project		580
Number of plants anticipated to retire based on stricter EPA regulations or new construction		6
Combined capacity of plants anticipated to retire based on stricter EPA regulations or new construction (in MW)	797	797
Amount currently authorized by Board of Directors to spend on Bell Bend COLA			162
Capitalized costs associated with licensing efforts			$ 137	$ 131