Segment and Related Information (Income Statement and Balance Sheet Data) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014 Integer		Dec. 31, 2013		Dec. 31, 2012
Segment Information (Numeric) [Abstract]
Number of reportable segments																	4
Income Statement Data
Revenues																	$ 11,499		$ 11,721		$ 12,132
Depreciation																	1,220		1,142		1,087
Amortization																	228		222		186
Unrealized (gains) losses on derivatives, and other hedging activities																	(175)		236		27
Interest Expenses																	1,024		994		951
Income from Continuing Operations Before Income Taxes																	2,364		1,260		2,009
Income Taxes																	781		163		518
Deferred income taxes and investment tax credits																	556		77		417
Net Income Attributable to PPL Shareowners	695	[1]	497	[1]	229	[1]	316	[1]	(98)	[1],[2]	410	[1]	405	[1]	413	[1]	1,737		1,130		1,526
Cash Flow [Abstract]
Expenditures for long-lived assets																	4,154		4,283		3,153
Balance Sheet Data
Assets	48,864								46,259								48,864		46,259
Segment (Numeric) [Abstract]
Loss on lease termination for Colstrip coal-fired electric generating facility, pre-tax																	0		697		0
Loss on lease termination for Colstrip coal-fired electric generating facility, after-tax																			413
Montana Hydroelectric Generating Facilities [Member]
Segment (Numeric) [Abstract]
Gain on the sale of Montana hydroelectric generation business, pre-tax																	237
Gain on the sale of Montana hydroelectric generation business, after-tax																	137
Kentucky Regulated [Member]
Income Statement Data
Depreciation																	354		334		346
Amortization																	25	[3]	22	[3]	27	[3]
Unrealized (gains) losses on derivatives, and other hedging activities																	12	[4]	12	[4]	11	[4]
Interest Expenses																	219		212		219
Income from Continuing Operations Before Income Taxes																	501		484		263
Income Taxes																	189	[5]	179	[5]	80	[5]
Deferred income taxes and investment tax credits																	449	[6]	254	[6]	136	[6]
Net Income Attributable to PPL Shareowners																	312		307		177
Cash Flow [Abstract]
Expenditures for long-lived assets																	1,262		1,434		768
Balance Sheet Data
Assets	13,062								12,016								13,062		12,016
Kentucky Regulated [Member] | Utility Service [Member]
Income Statement Data
Revenues																	3,168	[7]	2,976	[7]	2,759	[7]
United Kingdom Regulated [Member]
Income Statement Data
Revenues																	2,621		2,403		2,336
Depreciation																	337		300		279
Amortization																	17	[3]	19	[3]	15	[3]
Unrealized (gains) losses on derivatives, and other hedging activities																	(199)	[4]	44	[4]	52	[4]
Interest Expenses																	461		425		421
Income from Continuing Operations Before Income Taxes																	1,311		993		953
Income Taxes																	329	[5]	71	[5]	150	[5]
Deferred income taxes and investment tax credits																	94	[6]	(45)	[6]	26	[6]
Net Income Attributable to PPL Shareowners																	982		922		803
Cash Flow [Abstract]
Expenditures for long-lived assets																	1,438		1,280		1,016
Balance Sheet Data
Assets	16,005								15,895								16,005		15,895
United Kingdom Regulated [Member] | Utility Service [Member]
Income Statement Data
Revenues																	2,573	[7]	2,359	[7]	2,289	[7]
United Kingdom Regulated [Member] | Energy Related Businesses [Member]
Income Statement Data
Revenues																	48		44		47
Pennsylvania Regulated [Member]
Income Statement Data
Depreciation																	185		178		160
Amortization																	19	[3]	19	[3]	18	[3]
Interest Expenses																	122		108		99
Income from Continuing Operations Before Income Taxes																	423		317		204
Income Taxes																	160	[5]	108	[5]	68	[5]
Deferred income taxes and investment tax credits																	87	[6]	127	[6]	114	[6]
Net Income Attributable to PPL Shareowners																	263		209		132
Cash Flow [Abstract]
Expenditures for long-lived assets																	957		942		633
Balance Sheet Data
Assets	7,785								6,846								7,785		6,846
Pennsylvania Regulated [Member] | Utility Service [Member]
Income Statement Data
Revenues																	2,044	[7]	1,866	[7]	1,760	[7]
Supply [Member]
Income Statement Data
Revenues																	3,652		4,463		5,277
Depreciation																	297		299		276
Amortization																	163	[3]	156	[3]	126	[3]
Unrealized (gains) losses on derivatives, and other hedging activities																	12	[4]	180	[4]	(36)	[4]
Interest Expenses																	181		216		212
Income from Continuing Operations Before Income Taxes																	246	[4]	(477)	[4],[8]	589	[4]
Income Taxes																	93	[5]	(174)	[5]	220	[5]
Deferred income taxes and investment tax credits																	(110)	[6]	(291)	[6]	141	[6]
Net Income Attributable to PPL Shareowners																	307	[4],[9]	(272)	[4],[8]	414	[4]
Cash Flow [Abstract]
Expenditures for long-lived assets																	431		568		736
Balance Sheet Data
Assets	11,025								11,408								11,025		11,408
Segment (Numeric) [Abstract]
Gain on the sale of Montana hydroelectric generation business, after-tax																	137
Supply [Member] | Energy [Member]
Income Statement Data
Revenues																	3,051	[4]	3,936	[4]	4,816	[4]
Supply [Member] | Energy Related Businesses [Member]
Income Statement Data
Revenues																	601		527		461
Corporate And Other [Member]
Income Statement Data
Revenues																	14		13		0
Depreciation																	47		31		26
Amortization																	4	[3]	6	[3]	0
Interest Expenses																	41		33		0
Income from Continuing Operations Before Income Taxes																	(117)	[10]	(57)		0
Income Taxes																	10	[10],[5]	(21)	[5]	0
Deferred income taxes and investment tax credits																	36	[10],[6]	32	[6]	0
Net Income Attributable to PPL Shareowners																	(127)	[10]	(36)		0
Cash Flow [Abstract]
Expenditures for long-lived assets																	66		59		0
Balance Sheet Data
Assets	987	[11]							94	[11]							987	[11]	94	[11]
Intersegment Eliminations [Member] | Supply [Member]
Income Statement Data
Revenues																	(84)	[12]	(51)	[12]	(79)	[12]
PPL Energy Supply LLC [Member]
Income Statement Data
Depreciation																	297		299		272
Amortization																	163		156		119
Unrealized (gains) losses on derivatives, and other hedging activities																	4		171		(41)
Interest Expenses																	124		159		158
Income from Continuing Operations Before Income Taxes																	303		(420)		665
Income Taxes																	116	[13]	(159)	[13]	236	[13]
Net Income Attributable to PPL Shareowners																	410		(230)		474
Balance Sheet Data
Assets	10,760								11,074								10,760		11,074
Segment (Numeric) [Abstract]
Loss on lease termination for Colstrip coal-fired electric generating facility, pre-tax																	0		697		0
Loss on lease termination for Colstrip coal-fired electric generating facility, after-tax																			413
PPL Energy Supply LLC [Member] | Montana Hydroelectric Generating Facilities [Member]
Segment (Numeric) [Abstract]
Gain on the sale of Montana hydroelectric generation business, pre-tax																	306
Gain on the sale of Montana hydroelectric generation business, after-tax																	$ 137

[1] Quarterly results can vary depending on, among other things, weather and the forward pricing of power. Accordingly, comparisons among quarters of a year may not be indicative of overall trends and changes in operations.

[2] Fourth quarter of 2013 includes a charge for the termination of the lease of the Colstrip coal-fired electric generating facility in Montana. See Note 8 to the Financial Statements for additional information.

[3] Represents non-cash expense items that include amortization of nuclear fuel, regulatory assets, debt discounts and premiums, debt issuance costs, emission allowances and RECs.

[4] Includes unrealized gains and losses from economic activity. See Note 17 for additional information.

[5] Represents both current and deferred income taxes, including investment tax credits.

[6] Represents a non-cash expense item that is also included in "Income Taxes."

[7] See Note 1for additional information on Utility Revenue.

[8] 2013 includes a charge of $697 million ($413 million after tax) for the termination of the lease of the Colstrip coal-fired electric generating facility. See Note 8 for additional information.

[9] 2014 includes a gain of $237 million ($137 million after tax) on the sale of the Montana hydroelectric generating facilities. See Note 8 for additional information.

[10] 2014 includes most of the costs related to the anticipated spinoff of PPL Energy Supply, including deferred income tax expense, transaction and transition costs and separation benefits for PPL Services employees. See Note 8 for additional information.

[11] Primarily consists of unallocated items, including cash, PP&E and the elimination of inter-segment transactions. Increase in 2014 was primarily due to increased cash on hand.

[12] See "PLR Contracts/Purchase of Accounts Receivable" in Note 14 for a discussion of the basis of accounting between reportable segments.

[13] Excludes current and deferred federal and state tax expense recorded to Discontinued Operations of $109 million, $17 million and $27 million in 2014, 2013 and 2012. Also excludes federal and state tax expense (benefit) recorded to OCI of $(56) million, $47 million and $(267) million in 2014, 2013 and 2012.