LG&E & KU Energy 10-Q 3 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 25, 2018
Document Entity Information [Line Items]
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Amendment Flag	false
Entity Registrant Name	PPL Corp
Entity Central Index Key	922,224
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		699,042,874
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
PPL Electric Utilities Corp [Member]
Document Entity Information [Line Items]
Amendment Flag	false
Entity Registrant Name	PPL ELECTRIC UTILITIES CORP
Entity Central Index Key	317,187
Entity Well-known Seasoned Issuer	No
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		66,368,056
LG And E And KU Energy LLC [Member]
Document Entity Information [Line Items]
Amendment Flag	false
Entity Registrant Name	LG&E & KU Energy LLC
Entity Central Index Key	1,518,339
Entity Well-known Seasoned Issuer	No
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		0
Louisville Gas And Electric Co [Member]
Document Entity Information [Line Items]
Amendment Flag	false
Entity Registrant Name	LOUISVILLE GAS & ELECTRIC CO
Entity Central Index Key	60,549
Entity Well-known Seasoned Issuer	No
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		21,294,223
Kentucky Utilities Co [Member]
Document Entity Information [Line Items]
Amendment Flag	false
Entity Registrant Name	KENTUCKY UTILITIES CO
Entity Central Index Key	55,387
Entity Well-known Seasoned Issuer	No
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		37,817,878

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) shares in Thousands, $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Operating Revenues
Operating Revenues		$ 2,126	$ 1,951
Operation
Fuel		214	191
Energy purchases		241	215
Other operation and maintenance		468	470
Depreciation		269	242
Taxes, other than income		83	75
Total Operating Expenses		1,275	1,193
Operating Income		851	758
Other Income (Expense) - net		(43)	(9)
Interest Expense		239	217
Income Before Income Taxes		569	532
Income Taxes		117	129
Net Income		$ 452	$ 403
Net Income:
Basic (in dollars per share)		$ 0.65	$ 0.59
Diluted (in dollars per share)		0.65	0.59
Dividends Declared Per Share of Common Stock (in dollars per share)		$ 0.41	$ 0.395
Weighted-Average Shares of Common Stock Outstanding (in thousands)
Basic (in shares)		694,514	680,882
Diluted (in shares)		695,322	683,084
PPL Electric Utilities Corp [Member]
Operating Revenues
Operating Revenues		$ 639	$ 573
Operation
Energy purchases		161	146
Other operation and maintenance		133	163
Depreciation		85	75
Taxes, other than income		32	29
Total Operating Expenses		411	413
Operating Income		228	160
Other Income (Expense) - net		6	0
Interest Expense		37	33
Income Before Income Taxes		197	127
Income Taxes		49	48
Net Income	[1]	148	79
LG And E And KU Energy LLC [Member]
Operating Revenues
Operating Revenues		872	809
Operation
Fuel		214	191
Energy purchases		80	69
Other operation and maintenance		205	205
Depreciation		117	105
Taxes, other than income		17	16
Total Operating Expenses		633	586
Operating Income		239	223
Other Income (Expense) - net		(3)	(4)
Interest Expense		50	49
Interest Expense with Affiliate		5	4
Income Before Income Taxes		181	166
Income Taxes		39	63
Net Income	[2]	142	103
Louisville Gas And Electric Co [Member]
Operating Revenues
Retail and wholesale		407	374
Electric revenue from affiliate		12	17
Operating Revenues		419	391
Operation
Fuel		79	80
Energy purchases		76	64
Energy purchases from affiliate		6	2
Other operation and maintenance		89	85
Depreciation		48	44
Taxes, other than income		9	8
Total Operating Expenses		307	283
Operating Income		112	108
Other Income (Expense) - net		(1)	(4)
Interest Expense		18	17
Income Before Income Taxes		93	87
Income Taxes		21	33
Net Income	[1]	72	54
Kentucky Utilities Co [Member]
Operating Revenues
Retail and wholesale		465	435
Electric revenue from affiliate		6	2
Operating Revenues		471	437
Operation
Fuel		135	111
Energy purchases		4	5
Energy purchases from affiliate		12	17
Other operation and maintenance		105	108
Depreciation		68	60
Taxes, other than income		8	8
Total Operating Expenses		332	309
Operating Income		139	128
Other Income (Expense) - net		(3)	(2)
Interest Expense		25	24
Income Before Income Taxes		111	102
Income Taxes		24	39
Net Income	[2]	$ 87	$ 63
[1]	Net income equals comprehensive income.
[2]	Net income approximates comprehensive income.

CONDENSED CONSOLIDATED STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Net Income		$ 452	$ 403
Amounts arising during the period - gains (losses), net of tax (expense) benefit:
Foreign currency translation adjustments, net of tax		116	(24)
Qualifying derivatives, net of tax		(20)	(6)
Defined benefit plans:
Net actuarial gain (loss), net of tax		(1)	0
Reclassifications from AOCI - (gains) losses, net of tax expense (benefit):
Qualifying derivatives, net of tax		12	(1)
Defined benefit plans:
Net actuarial (gain) loss, net of tax		36	32
Total other comprehensive income		143	1
Comprehensive income		595	404
LG And E And KU Energy LLC [Member]
Net Income	[1]	142	103
Defined benefit plans:
Total other comprehensive income		$ 1	$ 2
[1]	Net income approximates comprehensive income.

CONDENSED CONSOLIDATED STATEME4

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Tax effect of foreign currency translation adjustments arising during the period	$ 0	$ (1)
Tax effect of qualifying derivatives arising during the period	4	2
Tax effect of defined benefit plans - net actuarial gain (loss) arising during period	0	0
Tax effect of qualifying derivatives reclassified from accumulated other comprehensive income (loss)	(2)	0
Tax effect of net actuarial (gain) loss reclassified from accumulated other comprehensive income (loss)	(9)	(9)
LG And E And KU Energy LLC [Member]
Tax effect of defined benefit plans - net actuarial gain (loss) arising during period	0	0
Tax effect of equity investees' other comprehensive income (loss) reclassified from accumulated other comprehensive income (loss)	0	0
Tax effect of prior service costs reclassified from accumulated other comprehensive income (loss)	0	0
Tax effect of net actuarial (gain) loss reclassified from accumulated other comprehensive income (loss)	$ (1)	$ (1)

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Cash Flows from Operating Activities
Net Income		$ 452	$ 403
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation		269	242
Amortization		21	23
Defined benefit plans - (income) expense		(50)	(19)
Deferred income taxes and investment tax credits		59	161
Unrealized losses on derivatives, and other hedging activities		85	35
Stock-based compensation expense		15	19
Other		(3)	(1)
Change in current assets and current liabilities
Accounts receivable		(71)	(43)
Accounts payable		(36)	(84)
Unbilled revenues		58	52
Fuel, materials and supplies		43	44
Prepayments		(73)	(110)
Taxes payable		22	(21)
Regulatory assets and liabilities, net		64	(17)
Other current liabilities		(120)	(60)
Other		23	22
Other operating activities
Defined benefit plans - funding		(150)	(520)
Other assets		(30)	5
Other liabilities		(12)	4
Net cash provided by operating activities		566	135
Cash Flows from Investing Activities
Expenditures for property, plant and equipment		(750)	(677)
Expenditures for intangible assets		(7)	(3)
Other investing activities		4	1
Net cash used in investing activities		(753)	(679)
Cash Flows from Financing Activities
Issuance of long-term debt		144	64
Issuance of common stock		100	73
Payment of common stock dividends		(273)	(258)
Net increase (decrease) in short-term debt		369	744
Other financing activities		(9)	(16)
Net cash provided by (used in) financing activities		331	607
Effect of Exchange Rate on Cash, Cash Equivalents and Restricted Cash		(2)	3
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash		142	66
Cash and Cash Equivalents at Beginning of Period		485
Cash and Cash Equivalents at End of Period		629
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		511	367
Cash, Cash Equivalents and Restricted Cash at End of Period		653	433
Supplemental Disclosures of Cash Flow Information
Accrued expenditures for property, plant and equipment at March 31,		313	236
Accrued expenditures for intangible assets at March 31,		65	62
PPL Electric Utilities Corp [Member]
Cash Flows from Operating Activities
Net Income	[1]	148	79
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation		85	75
Amortization		6	8
Defined benefit plans - (income) expense		2	5
Deferred income taxes and investment tax credits		21	41
Other		(5)	0
Change in current assets and current liabilities
Accounts receivable		(30)	(27)
Accounts payable		(36)	(18)
Unbilled revenues		16	12
Prepayments		(69)	(75)
Taxes payable		4	0
Regulatory assets and liabilities, net		5	(11)
Other		(19)	(14)
Other operating activities
Defined benefit plans - funding		(28)	(24)
Other assets		(25)	5
Other liabilities		1	(1)
Net cash provided by operating activities		76	55
Cash Flows from Investing Activities
Expenditures for property, plant and equipment		(245)	(274)
Expenditures for intangible assets		(1)	(2)
Net cash used in investing activities		(246)	(276)
Cash Flows from Financing Activities
Net increase (decrease) in short-term debt		213	204
Contributions from parent		0	100
Payment of common stock dividends to parent		(72)	(76)
Net cash provided by (used in) financing activities		141	228
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash		(29)	7
Cash and Cash Equivalents at Beginning of Period		49
Cash and Cash Equivalents at End of Period		20
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		51	15
Cash, Cash Equivalents and Restricted Cash at End of Period		22	22
Supplemental Disclosures of Cash Flow Information
Accrued expenditures for property, plant and equipment at March 31,		147	122
LG And E And KU Energy LLC [Member]
Cash Flows from Operating Activities
Net Income	[2]	142	103
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation		117	105
Amortization		5	7
Defined benefit plans - (income) expense		3	8
Deferred income taxes and investment tax credits		8	48
Change in current assets and current liabilities
Accounts receivable		(5)	21
Accounts payable		10	(28)
Accounts payable to affiliates		2	7
Unbilled revenues		31	22
Fuel, materials and supplies		42	41
Taxes payable		7	(2)
Accrued interest		42	42
Other		(7)	(38)
Other operating activities
Defined benefit plans - funding		(108)	(22)
Expenditures for asset retirement obligations		(9)	(6)
Other assets		(3)	1
Other liabilities		1	3
Net cash provided by operating activities		278	312
Cash Flows from Investing Activities
Expenditures for property, plant and equipment		(294)	(184)
Net cash used in investing activities		(294)	(184)
Cash Flows from Financing Activities
Net increase (decrease) in notes payable with affiliate		12	(81)
Issuance of long-term debt		100	0
Distributions to member		(69)	(102)
Net increase (decrease) in short-term debt		(29)	58
Other financing activities		(1)	(1)
Net cash provided by (used in) financing activities		13	(126)
Cash and Cash Equivalents, Period Increase (Decrease)		(3)	2
Cash and Cash Equivalents at Beginning of Period		30	13
Cash and Cash Equivalents at End of Period		27	15
Supplemental Disclosures of Cash Flow Information
Accrued expenditures for property, plant and equipment at March 31,		124	75
Louisville Gas And Electric Co [Member]
Cash Flows from Operating Activities
Net Income	[1]	72	54
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation		48	44
Amortization		4	3
Defined benefit plans - (income) expense		1	2
Deferred income taxes and investment tax credits		7	31
Change in current assets and current liabilities
Accounts receivable		2	13
Accounts receivable from affiliates		(7)	1
Accounts payable		8	(12)
Accounts payable to affiliates		(2)	(4)
Unbilled revenues		16	9
Fuel, materials and supplies		36	33
Taxes payable		(1)	(28)
Accrued interest		13	13
Other		12	(11)
Other operating activities
Defined benefit plans - funding		(55)	(1)
Expenditures for asset retirement obligations		(5)	(4)
Other assets		0	2
Other liabilities		(3)	(3)
Net cash provided by operating activities		146	142
Cash Flows from Investing Activities
Expenditures for property, plant and equipment		(150)	(94)
Net cash used in investing activities		(150)	(94)
Cash Flows from Financing Activities
Issuance of long-term debt		100	0
Net increase (decrease) in short-term debt		(62)	38
Payment of common stock dividends to parent		(34)	(87)
Other financing activities		(1)	0
Net cash provided by (used in) financing activities		3	(49)
Cash and Cash Equivalents, Period Increase (Decrease)		(1)	(1)
Cash and Cash Equivalents at Beginning of Period		15	5
Cash and Cash Equivalents at End of Period		14	4
Supplemental Disclosures of Cash Flow Information
Accrued expenditures for property, plant and equipment at March 31,		75	34
Kentucky Utilities Co [Member]
Cash Flows from Operating Activities
Net Income	[2]	87	63
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation		68	60
Amortization		1	4
Defined benefit plans - (income) expense		0	2
Deferred income taxes and investment tax credits		1	37
Change in current assets and current liabilities
Accounts receivable		(7)	8
Accounts payable		11	(4)
Accounts payable to affiliates		0	(7)
Unbilled revenues		15	13
Fuel, materials and supplies		6	8
Taxes payable		14	(34)
Accrued interest		22	22
Other		17	(12)
Other operating activities
Defined benefit plans - funding		(47)	(19)
Expenditures for asset retirement obligations		(4)	(2)
Other assets		(3)	(1)
Other liabilities		4	1
Net cash provided by operating activities		185	139
Cash Flows from Investing Activities
Expenditures for property, plant and equipment		(143)	(89)
Net cash used in investing activities		(143)	(89)
Cash Flows from Financing Activities
Net increase (decrease) in short-term debt		33	20
Payment of common stock dividends to parent		(79)	(70)
Net cash provided by (used in) financing activities		(46)	(50)
Cash and Cash Equivalents, Period Increase (Decrease)		(4)	0
Cash and Cash Equivalents at Beginning of Period		15	7
Cash and Cash Equivalents at End of Period		11	7
Supplemental Disclosures of Cash Flow Information
Accrued expenditures for property, plant and equipment at March 31,		$ 48	$ 41
[1]	Net income equals comprehensive income.
[2]	Net income approximates comprehensive income.

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Millions		Mar. 31, 2018	Dec. 31, 2017
Assets, Current [Abstract]
Cash and cash equivalents		$ 629	$ 485
Accounts receivable (less reserve:)
Customer		760	681
Other		89	100
Unbilled revenues		489	543
Prepayments		139	66
Fuel, materials and supplies		279	320
Price risk management assets		56	49
Regulatory assets		28	34
Other current assets		49	50
Total Current Assets		2,490	2,294
Property, Plant and Equipment
Regulated utility plant		38,891	38,228
Less: accumulated depreciation - regulated utility plant		7,003	6,785
Regulated utility plant, net		31,888	31,443
Non-regulated property, plant and equipment		387	384
Less: accumulated depreciation - non-regulated property, plant and equipment		114	110
Non-regulated property, plant and equipment, net		273	274
Construction work in progress		1,575	1,375
Property, Plant and Equipment, net		33,736	33,092
Other Noncurrent Assets
Regulatory assets		1,519	1,504
Goodwill		3,302	3,258
Other intangibles		703	697
Pension benefit asset		378	284
Price risk management assets		120	215
Other noncurrent assets		140	135
Total Other Noncurrent Assets		6,162	6,093
Total Assets		42,388	41,479
Current Liabilities
Short-term debt		1,457	1,080
Long-term debt due within one year		250	348
Accounts payable		836	924
Taxes		128	105
Interest		323	282
Dividends		285	273
Customer deposits		286	292
Regulatory liabilities		158	95
Other current liabilities		515	624
Total Current Liabilities		4,238	4,023
Long-term Debt
Long-term Debt		20,214	19,847
Deferred Credits and Other Noncurrent Liabilities
Deferred income taxes		2,557	2,462
Investment tax credits		128	129
Accrued pension obligations		653	800
Asset retirement obligations		292	312
Regulatory liabilities		2,689	2,704
Other deferred credits and noncurrent liabilities		441	441
Total Deferred Credits and Other Noncurrent Liabilities		6,760	6,848
Commitments and Contingent Liabilities
Equity
Common stock	[1]	7	7
Additional paid-in capital		10,411	10,305
Earnings reinvested		4,037	3,871
Accumulated other comprehensive loss		(3,279)	(3,422)
Total Equity		11,176	10,761
Total Liabilities and Equity		42,388	41,479
PPL Electric Utilities Corp [Member]
Assets, Current [Abstract]
Cash and cash equivalents		20	49
Accounts receivable (less reserve:)
Customer		328	279
Other		10	71
Accounts receivable from affiliates		42	0
Unbilled revenues		111	127
Prepayments		75	6
Fuel, materials and supplies		34	34
Regulatory assets		16	16
Other current assets		12	6
Total Current Assets		648	588
Property, Plant and Equipment
Regulated utility plant		10,950	10,785
Less: accumulated depreciation - regulated utility plant		2,815	2,778
Regulated utility plant, net		8,135	8,007
Construction work in progress		560	508
Property, Plant and Equipment, net		8,695	8,515
Other Noncurrent Assets
Regulatory assets		726	709
Other intangibles		259	259
Other noncurrent assets		15	11
Total Other Noncurrent Assets		1,000	979
Total Assets		10,343	10,082
Current Liabilities
Short-term debt		213	0
Accounts payable		362	386
Accounts payable to affiliates		32	31
Taxes		12	8
Interest		38	36
Regulatory liabilities		95	86
Other current liabilities		83	98
Total Current Liabilities		835	645
Long-term Debt
Long-term Debt		3,298	3,298
Deferred Credits and Other Noncurrent Liabilities
Deferred income taxes		1,184	1,154
Accrued pension obligations		215	246
Regulatory liabilities		662	668
Other deferred credits and noncurrent liabilities		81	79
Total Deferred Credits and Other Noncurrent Liabilities		2,142	2,147
Commitments and Contingent Liabilities
Equity
Common stock	[2]	364	364
Additional paid-in capital		2,729	2,729
Earnings reinvested		975	899
Total Equity		4,068	3,992
Total Liabilities and Equity		10,343	10,082
LG And E And KU Energy LLC [Member]
Assets, Current [Abstract]
Cash and cash equivalents		27	30
Accounts receivable (less reserve:)
Customer		247	246
Other		41	44
Accounts receivable from affiliates		1	0
Unbilled revenues		172	203
Prepayments		28	25
Fuel, materials and supplies		212	254
Regulatory assets		12	18
Other current assets		5	8
Total Current Assets		745	828
Property, Plant and Equipment
Regulated utility plant		13,226	13,187
Less: accumulated depreciation - regulated utility plant		1,866	1,785
Regulated utility plant, net		11,360	11,402
Construction work in progress		775	627
Property, Plant and Equipment, net		12,135	12,029
Other Noncurrent Assets
Regulatory assets		793	795
Goodwill		996	996
Other intangibles		84	86
Other noncurrent assets		81	68
Total Other Noncurrent Assets		1,954	1,945
Total Assets		14,834	14,802
Current Liabilities
Short-term debt		215	244
Long-term debt due within one year		0	98
Notes payable with affiliates		237	225
Accounts payable		292	338
Accounts payable to affiliates		9	7
Taxes		73	66
Price risk management liabilities		4	4
Interest		74	32
Customer deposits		59	58
Regulatory liabilities		63	9
Asset retirement obligations		91	85
Other current liabilities		94	161
Total Current Liabilities		1,211	1,327
Long-term Debt
Long-term debt		4,859	4,661
Long-term debt to affiliate		400	400
Long-term Debt		5,259	5,061
Deferred Credits and Other Noncurrent Liabilities
Deferred income taxes		882	866
Investment tax credits		128	129
Accrued pension obligations		265	365
Asset retirement obligations		249	271
Regulatory liabilities		2,027	2,036
Price risk management liabilities		18	22
Other deferred credits and noncurrent liabilities		158	162
Total Deferred Credits and Other Noncurrent Liabilities		3,727	3,851
Commitments and Contingent Liabilities
Equity
Member's Equity		4,637	4,563
Total Liabilities and Equity		14,834	14,802
Louisville Gas And Electric Co [Member]
Assets, Current [Abstract]
Cash and cash equivalents		14	15
Accounts receivable (less reserve:)
Customer		111	116
Other		14	13
Accounts receivable from affiliates		31	24
Unbilled revenues		75	91
Prepayments		12	11
Fuel, materials and supplies		95	131
Regulatory assets		10	12
Other current assets		1	3
Total Current Assets		363	416
Property, Plant and Equipment
Regulated utility plant		5,597	5,587
Less: accumulated depreciation - regulated utility plant		646	614
Regulated utility plant, net		4,951	4,973
Construction work in progress		401	305
Property, Plant and Equipment, net		5,352	5,278
Other Noncurrent Assets
Regulatory assets		406	411
Goodwill		389	389
Other intangibles		51	53
Other noncurrent assets		26	12
Total Other Noncurrent Assets		872	865
Total Assets		6,587	6,559
Current Liabilities
Short-term debt		137	199
Long-term debt due within one year		0	98
Accounts payable		170	179
Accounts payable to affiliates		21	23
Taxes		24	25
Price risk management liabilities		4	4
Interest		24	11
Customer deposits		28	27
Regulatory liabilities		29	3
Asset retirement obligations		19	24
Other current liabilities		34	52
Total Current Liabilities		490	645
Long-term Debt
Long-term Debt		1,808	1,611
Deferred Credits and Other Noncurrent Liabilities
Deferred income taxes		582	572
Investment tax credits		35	35
Accrued pension obligations		0	45
Asset retirement obligations		92	97
Regulatory liabilities		912	919
Price risk management liabilities		18	22
Other deferred credits and noncurrent liabilities		85	86
Total Deferred Credits and Other Noncurrent Liabilities		1,724	1,776
Commitments and Contingent Liabilities
Equity
Common stock	[3]	424	424
Additional paid-in capital		1,712	1,712
Earnings reinvested		429	391
Total Equity		2,565	2,527
Total Liabilities and Equity		6,587	6,559
Kentucky Utilities Co [Member]
Assets, Current [Abstract]
Cash and cash equivalents		11	15
Accounts receivable (less reserve:)
Customer		136	130
Other		26	30
Unbilled revenues		97	112
Prepayments		14	14
Fuel, materials and supplies		117	123
Regulatory assets		2	6
Other current assets		4	5
Total Current Assets		407	435
Property, Plant and Equipment
Regulated utility plant		7,620	7,592
Less: accumulated depreciation - regulated utility plant		1,218	1,170
Regulated utility plant, net		6,402	6,422
Construction work in progress		373	321
Property, Plant and Equipment, net		6,775	6,743
Other Noncurrent Assets
Regulatory assets		387	384
Goodwill		607	607
Other intangibles		33	33
Other noncurrent assets		67	52
Total Other Noncurrent Assets		1,094	1,076
Total Assets		8,276	8,254
Current Liabilities
Short-term debt		78	45
Accounts payable		109	137
Accounts payable to affiliates		54	53
Taxes		33	19
Interest		38	16
Customer deposits		31	31
Regulatory liabilities		34	6
Asset retirement obligations		72	61
Other current liabilities		30	46
Total Current Liabilities		479	414
Long-term Debt
Long-term Debt		2,329	2,328
Deferred Credits and Other Noncurrent Liabilities
Deferred income taxes		696	691
Investment tax credits		93	94
Accrued pension obligations		0	36
Asset retirement obligations		157	174
Regulatory liabilities		1,115	1,117
Other deferred credits and noncurrent liabilities		42	43
Total Deferred Credits and Other Noncurrent Liabilities		2,103	2,155
Commitments and Contingent Liabilities
Equity
Common stock	[4]	308	308
Additional paid-in capital		2,616	2,616
Earnings reinvested		441	433
Total Equity		3,365	3,357
Total Liabilities and Equity		$ 8,276	$ 8,254
[1]	1,560,000 shares authorized; 697,383 and 693,398 shares issued and outstanding at March 31, 2018 and December 31, 2017.
[2]	170,000 shares authorized; 66,368 shares issued and outstanding at March 31, 2018 and December 31, 2017.
[3]	75,000 shares authorized; 21,294 shares issued and outstanding at March 31, 2018 and December 31, 2017.
[4]	80,000 shares authorized; 37,818 shares issued and outstanding at March 31, 2018 and December 31, 2017.

CONDENSED CONSOLIDATED BALANCE7

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) shares in Thousands, $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Receivables, Net, Current [Abstract]
Accounts receivable reserve for doubtful accounts	$ 56	$ 51
Equity
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock shares authorized (in shares)	1,560,000	1,560,000
Common stock shares issued (in shares)	697,383	693,398
Common stock shares outstanding (in shares)	697,383	693,398
PPL Electric Utilities Corp [Member]
Receivables, Net, Current [Abstract]
Accounts receivable reserve for doubtful accounts	$ 27	$ 24
Equity
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock shares authorized (in shares)	170,000	170,000
Common stock shares issued (in shares)	66,368	66,368
Common stock shares outstanding (in shares)	66,368	66,368
LG And E And KU Energy LLC [Member]
Receivables, Net, Current [Abstract]
Accounts receivable reserve for doubtful accounts	$ 26	$ 25
Louisville Gas And Electric Co [Member]
Receivables, Net, Current [Abstract]
Accounts receivable reserve for doubtful accounts	$ 1	$ 1
Equity
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock shares authorized (in shares)	75,000	75,000
Common stock shares issued (in shares)	21,294	21,294
Common stock shares outstanding (in shares)	21,294	21,294
Kentucky Utilities Co [Member]
Receivables, Net, Current [Abstract]
Accounts receivable reserve for doubtful accounts	$ 2	$ 1
Equity
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock shares authorized (in shares)	80,000	80,000
Common stock shares issued (in shares)	37,818	37,818
Common stock shares outstanding (in shares)	37,818	37,818

CONDENSED CONSOLIDATED STATEME8

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) - USD ($) shares in Thousands, $ in Millions		Total	Common Stock [Member]		Additional Paid-in Capital [Member]	Earnings Reinvested [Member]	Accumulated Other Comprehensive Loss [Member]	PPL Electric Utilities Corp [Member]		PPL Electric Utilities Corp [Member]Common Stock [Member]		PPL Electric Utilities Corp [Member]Additional Paid-in Capital [Member]	PPL Electric Utilities Corp [Member]Earnings Reinvested [Member]	LG And E And KU Energy LLC [Member]		Louisville Gas And Electric Co [Member]		Louisville Gas And Electric Co [Member]Common Stock [Member]		Louisville Gas And Electric Co [Member]Additional Paid-in Capital [Member]	Louisville Gas And Electric Co [Member]Earnings Reinvested [Member]	Kentucky Utilities Co [Member]		Kentucky Utilities Co [Member]Common Stock [Member]		Kentucky Utilities Co [Member]Additional Paid-in Capital [Member]	Kentucky Utilities Co [Member]Earnings Reinvested [Member]	Kentucky Utilities Co [Member]Accumulated Other Comprehensive Loss [Member]
Balance at beginning of period - shares at Dec. 31, 2016			679,731	[1]						66,368	[2]							21,294	[3]					37,818	[4]
Balance at beginning of period at Dec. 31, 2016		$ 9,899	$ 7		$ 9,841	$ 3,829	$ (3,778)	$ 3,391		$ 364		$ 2,154	$ 873			$ 2,476		$ 424		$ 1,682	$ 370	$ 3,323		$ 308		$ 2,616	$ 400	$ (1)
Balance at beginning of period at Dec. 31, 2016														$ 4,667
Common stock shares issued	[1]		2,696
Common stock issued		97			97
Stock-based compensation		(21)			(21)
Net Income		403				403		79	[5]				79	103	[6]	54	[5]				54	63	[6]				63
Capital contributions from parent								100				100
Dividends and dividend equivalents		(270)				(270)
Dividends declared on common stock								(76)					(76)			(87)					(87)	(70)					(70)
Distributions to member														(102)
Other comprehensive income (loss)		1					1							2								1						1
Balance at end of period - shares at Mar. 31, 2017			682,427	[1]						66,368	[2]							21,294	[3]					37,818	[4]
Balance at end of period at Mar. 31, 2017		$ 10,109	$ 7		9,917	3,962	(3,777)	$ 3,494		$ 364		2,254	876			$ 2,443		$ 424		1,682	337	$ 3,317		$ 308		2,616	393	0
Balance at end of period at Mar. 31, 2017														4,670
Balance at beginning of period - shares at Dec. 31, 2017		693,398	693,398	[1]				66,368		66,368	[2]					21,294		21,294	[3]			37,818		37,818	[4]
Balance at beginning of period at Dec. 31, 2017		$ 10,761	$ 7		10,305	3,871	(3,422)	$ 3,992		$ 364		2,729	899			$ 2,527		$ 424		1,712	391	$ 3,357		$ 308		2,616	433	0
Balance at beginning of period at Dec. 31, 2017														4,563
Common stock shares issued	[1]		3,985
Common stock issued		115			115
Stock-based compensation		(9)			(9)
Net Income		452				452		148	[5]				148	142	[6]	72	[5]				72	87	[6]				87
Dividends and dividend equivalents		(286)				(286)
Dividends declared on common stock								$ (72)					(72)			$ (34)					(34)	$ (79)					(79)
Distributions to member														(69)
Other comprehensive income (loss)		$ 143					143							1
Balance at end of period - shares at Mar. 31, 2018		697,383	697,383	[1]				66,368		66,368	[2]					21,294		21,294	[3]			37,818		37,818	[4]
Balance at end of period at Mar. 31, 2018		$ 11,176	$ 7		$ 10,411	$ 4,037	$ (3,279)	$ 4,068		$ 364		$ 2,729	$ 975			$ 2,565		$ 424		$ 1,712	$ 429	$ 3,365		$ 308		$ 2,616	$ 441	$ 0
Balance at end of period at Mar. 31, 2018														$ 4,637
[1]	Shares in thousands. Each share entitles the holder to one vote on any question presented at any shareowners' meeting.
[2]	Shares in thousands. All common shares of PPL Electric stock are owned by PPL.
[3]	Shares in thousands. All common shares of LG&E stock are owned by LKE.
[4]	Shares in thousands. All common shares of KU stock are owned by LKE.
[5]	Net income equals comprehensive income.
[6]	Net income approximates comprehensive income.

CONDENSED CONSOLIDATED STATEME9

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) (Parenthetical)	3 Months Ended
	Mar. 31, 2018vote
Vote per share of PPL's common stock	1

Interim Financial Statements

Interim Financial Statements	3 Months Ended
	Mar. 31, 2018
Interim Financial Statements [Abstract]
Interim Financial Statements	1. Interim Financial Statements (All Registrants) Capitalized terms and abbreviations appearing in the unaudited combined notes to condensed financial statements are defined in the glossary. Dollars are in millions, except per share data, unless otherwise noted. The specific Registrant to which disclosures are applicable is identified in parenthetical headings in italics above the applicable disclosure or within the applicable disclosure for each Registrants' related activities and disclosures. Within combined disclosures, amounts are disclosed for any Registrant when significant. The accompanying unaudited condensed financial statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X and, therefore, do not include all of the information and footnote disclosures required by GAAP for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation in accordance with GAAP are reflected in the condensed financial statements. All adjustments are of a normal recurring nature, except as otherwise disclosed. Each Registrant's Balance Sheet at December 31, 2017 is derived from that Registrant's 2017 audited Balance Sheet. The financial statements and notes thereto should be read in conjunction with the financial statements and notes contained in each Registrant's 2017 Form 10-K. The results of operations for the three months ended March 31, 2018 are not necessarily indicative of the results to be expected for the full year ending December 31, 2018 or other future periods, because results for interim periods can be disproportionately influenced by various factors, developments and seasonal variations.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies (All Registrants) The following accounting policy disclosures represent updates to Note 1 in each indicated Registrant's 2017 Form 10-K and should be read in conjunction with those disclosures. New Accounting Guidance Adopted (All Registrants) Accounting for Revenue from Contracts with Customers Effective January 1, 2018, the Registrants adopted accounting guidance that establishes a comprehensive new model for the recognition of revenue from contracts with customers. This model is based on the core principle that revenue should be recognized to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The Registrants adopted this guidance using the modified retrospective transition method. No cumulative effect adjustment was required as of the January 1, 2018 adoption date. The adoption of this guidance did not have a material impact on the Registrants' revenue recognition policies. See Note 4 for the required disclosures as a result of the adoption of this standard. Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost Effective January 1, 2018, the Registrants adopted accounting guidance that changes the income statement presentation of net periodic benefit cost. Retrospectively, this guidance requires the service cost component to be disaggregated from other components of net benefit cost and presented in the same income statement line items as other employee compensation costs arising from services rendered during the period. The other components of net periodic benefits are presented separately from the line items that include the service cost and outside of any subtotal of operating income. Prospectively, the guidance limits the capitalization to the service cost component of net periodic benefit costs. For PPL, the non-service cost components of net periodic benefit costs are in a net credit position for the three months ended March 31, 2018. The non-service cost credits that would have been capitalized under previous guidance, but are now recorded as income within "Other Income (Expense) - net," were $5 million ( $4 million after-tax or $0.01 per share) for the three months ended March 31, 2018. For PPL Electric, LG&E and KU, non-service costs or credits that would have been capitalized under previous guidance are now recognized as a regulatory asset or regulatory liability, as applicable, in accordance with regulatory approvals. The following provides the non-service cost components of net periodic benefits (costs) or credits presented in "Other Income (Expense) - net" in 2018 and reclassified from "Other operation and maintenance" to "Other Income (Expense) - net" in 2017 on the Statements of Income as a result of the adoption. Three Months 2018 2017 PPL $ 68 $ 38 PPL Electric 2 (1 ) LKE 2 (2 ) LG&E 1 (2 ) KU 1 (1 ) PPL and PPL Electric elected to use the practical expedient that permits using the amounts disclosed in the defined benefit plan note for the prior comparative period as the estimation basis for applying the retrospective presentation requirements. Presentation of Restricted Cash in the Statement of Cash Flows (PPL and PPL Electric) Effective January 1, 2018, PPL and PPL Electric adopted accounting guidance that changes the cash flow statement presentation of restricted cash. Under the new guidance, amounts considered restricted cash are presented with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total cash amounts on the Statements of Cash Flows. The guidance requires a reconciliation of the total cash, cash equivalents and restricted cash from the Statement of Cash Flows to amounts on the Balance Sheets and disclosure of the nature of the restrictions. PPL and PPL Electric have applied this guidance on a retrospective basis for all periods presented. The adoption of this guidance did not have a material impact on the Statements of Cash Flows. Reconciliation of Cash, Cash Equivalents and Restricted Cash The following provides a reconciliation of Cash, Cash Equivalents and Restricted Cash reported within the Balance Sheets that sum to the total of the same amounts shown on the Statements of Cash Flows: PPL PPL Electric March 31, 2018 December 31, 2017 March 31, 2018 December 31, 2017 Cash and cash equivalents $ 629 $ 485 $ 20 $ 49 Restricted cash - current (a) 3 3 2 2 Restricted cash - noncurrent (a) 21 23 — — Total Cash, Cash Equivalents and Restricted Cash $ 653 $ 511 $ 22 $ 51 (a) Bank deposits and other cash equivalents that are restricted by agreement or that have been clearly designated for a specific purpose are classified as restricted cash. On the Balance Sheets, the current portion of restricted cash is included in "Other current assets," while the noncurrent portion is included in "Other noncurrent assets."

Segment and Related Information

Segment and Related Information	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Segment and Related Information	3. Segment and Related Information (PPL) See Note 2 in PPL's 2017 Form 10-K for a discussion of reportable segments and related information. Income Statement data for the segments and reconciliation to PPL's consolidated results for the periods ended March 31 are as follows: Three Months 2018 2017 Operating Revenues from external customers U.K. Regulated $ 615 $ 568 Kentucky Regulated 872 809 Pennsylvania Regulated 639 573 Corporate and Other — 1 Total $ 2,126 $ 1,951 Net Income U.K. Regulated (a) $ 197 $ 286 Kentucky Regulated 133 95 Pennsylvania Regulated 148 79 Corporate and Other (26 ) (57 ) Total $ 452 $ 403 (a) Includes unrealized gains and losses from hedging foreign currency economic activity. See Note 14 for additional information. The following provides Balance Sheet data for the segments and reconciliation to PPL's consolidated results as of: March 31, December 31, Assets U.K. Regulated (a) $ 17,444 $ 16,813 Kentucky Regulated 14,500 14,468 Pennsylvania Regulated 10,356 10,082 Corporate and Other (b) 88 116 Total $ 42,388 $ 41,479 (a) Includes $12.9 billion and $12.5 billion of net PP&E as of March 31, 2018 and December 31, 2017 . WPD is not subject to accounting for the effects of certain types of regulation as prescribed by GAAP. (b) Primarily consists of unallocated items, including cash, PP&E and the elimination of inter-segment transactions. (PPL Electric, LKE, LG&E and KU) PPL Electric has two operating segments that are aggregated into a single reportable segment. LKE, LG&E and KU are individually single operating and reportable segments.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	3 Months Ended
	Mar. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	4. Revenue from Contracts with Customers (All Registrants) The following is a description of the principal activities from which the Registrants and PPL’s segments generate their revenues. U.K. Regulated Segment Revenue (PPL) The U.K. Regulated Segment generates revenues from contracts with customers primarily from WPD’s DUoS operations. DUoS revenues result from WPD charging licensed third-party energy suppliers for their use of WPD’s distribution systems to deliver energy to their customers. WPD satisfies its performance obligation and DUoS revenue is recognized over-time as electricity is delivered. The amount of revenue recognized is the volume of electricity delivered during the period multiplied by a per-unit energy tariff, plus fixed charges. This method of recognition fairly presents WPD's transfer of electric service to the customer as the calculation is based on actual volumes, and the tariff rate is set by WPD using a methodology prescribed by Ofgem. Customers are billed monthly and outstanding amounts are typically due within 14 days of the invoice date. DUoS customers are “at will” customers of WPD with no term contract and no minimum purchase commitment. Performance obligations are limited to the service requested and received to date. Accordingly, there is no unsatisfied performance obligation associated with WPD’s DUoS contracts. Pennsylvania Regulated Segment Revenue (PPL and PPL Electric) The Pennsylvania Regulated Segment generates substantially all of its revenues from contracts with customers from PPL Electric’s tariff-based distribution and transmission of electricity. Distribution Revenue PPL Electric provides distribution services to residential, commercial, industrial, municipal and governmental end users of energy. PPL Electric satisfies its performance obligation to its distribution customers and revenue is recognized over-time as electricity is delivered and simultaneously consumed by the customer. The amount of revenue recognized is the volume of electricity delivered during the period multiplied by a per-unit of energy tariff, plus a monthly fixed charge. This method of recognition fairly presents PPL Electric's transfer of electric service to the customer as the calculation is based on actual volumes, and the per-unit of energy tariff rate and the monthly fixed charge are set by the PUC. Customers are typically billed monthly and outstanding amounts are typically due within 21 days of the date of the bill. Distribution customers are "at will" customers of PPL Electric with no term contract and no minimum purchase commitment. Performance obligations are limited to the service requested and received to date. Accordingly, there is no unsatisfied performance obligation associated with PPL Electric’s retail account contracts. Transmission Revenue PPL Electric generates transmission revenues from a FERC-approved PJM Open Access Transmission Tariff. An annual revenue requirement for PPL Electric to provide transmission services is calculated using a formula-based rate. This revenue requirement is converted into a daily rate (dollars per day). PPL Electric satisfies its performance obligation to provide transmission services and revenue is recognized over-time as transmission services are provided and consumed. This method of recognition fairly presents PPL Electric's transfer of transmission services as the daily rate is set by a FERC approved formula-based rate. PJM remits payment on a weekly basis. PPL Electric's agreement to provide transmission services contains no minimum purchase commitment. The performance obligation is limited to the service requested and received to date. Accordingly, PPL Electric has no unsatisfied performance obligations. Kentucky Regulated Segment Revenue (PPL, LKE, LG&E and KU) The Kentucky Regulated Segment generates substantially all of its revenues from contracts with customers primarily from LG&E's and KU's regulated tariff-based sales of electricity and LG&E's regulated tariff-based sales of natural gas. LG&E and KU are engaged in the generation, transmission, distribution and sale of electricity in Kentucky and, in KU's case, Virginia. LG&E also engages in the distribution and sale of natural gas in Kentucky. Revenue from these activities is generated from tariffs approved by applicable regulatory authorities including the FERC, KPSC and VSCC. LG&E and KU satisfy their performance obligations upon LG&E's and KU's delivery of electricity and LG&E's delivery of natural gas to customers. This revenue is recognized over-time as the customer simultaneously receives and consumes the benefits provided by LG&E and KU. The amount of revenue recognized is the billed volume of electricity or natural gas delivered multiplied by a tariff rate per-unit of energy, plus any applicable fixed charges or additional regulatory mechanisms. Customers are billed monthly and outstanding amounts are typically due within 22 days of the date of the bill. Additionally, unbilled revenues are recognized as a result of customers' bills rendered throughout the month, rather than bills being rendered at the end of the month. Unbilled revenues for a month are calculated by multiplying an estimate of unbilled kWh or Mcf delivered but not yet billed by the estimated average cents per kWh or Mcf. Any difference between estimated and actual revenues is adjusted the following month when the previous unbilled estimate is reversed and actual billings occur. This method of recognition fairly presents LG&E's and KU's transfer of electricity and LG&E's transfer of natural gas to the customer as the amount recognized is based on actual or estimated volumes delivered and the tariff rate per-unit of energy and any applicable fixed charges or regulatory mechanisms as set by the respective regulatory body. LG&E's and KU's customers primarily have no minimum purchase commitment. Performance obligations are limited to the service requested and received to date. Accordingly, there is no unsatisfied performance obligation associated with these customers. (All Registrants) The following table reconciles "Operating Revenues" included in each Registrant's Statement of Income with revenues generated from contracts with customers for the period ended March 31, 2018. Three Months PPL PPL Electric LKE LG&E KU Operating Revenues (a) $ 2,126 $ 639 $ 872 $ 419 $ 471 Revenues derived from: Alternative revenue programs (b) 32 2 30 14 16 Other (c) (16 ) (4 ) (5 ) (1 ) (4 ) Revenues from Contracts with Customers $ 2,142 $ 637 $ 897 $ 432 $ 483 (a) PPL includes $615 million of revenues from external customers reported by the U.K. Regulated segment. PPL Electric and LKE represent revenues from external customers reported by the Pennsylvania Regulated and Kentucky Regulated segments. See Note 3 for additional information. (b) Alternative revenue programs for PPL Electric include the over/under-collection of its transmission formula rate. Alternative revenue programs for LKE, LG&E and KU include the over/under collection for the ECR and DSM programs as well as LG&E's over/under collection of its GLT program and KU's over/under collection of its generation formula rate. Over-collections of revenue are shown as positive amounts in the table above; under-collections are shown as negative amounts. (c) Represents additional revenues outside the scope of revenues from contracts with customers such as leases and other miscellaneous revenues. As discussed in Note 3, PPL's segments are segmented by geographic location. Revenues from external customers for each segment/geographic location are reconciled to revenues from contracts with customers in the table above. For PPL Electric, revenues from contracts with customers are further disaggregated by distribution and transmission, which were $532 million and $105 million for the three months ended March 31, 2018. The following table shows revenues from contracts with customers disaggregated by customer class for the period ended March 31, 2018 . Three Months PPL PPL Electric LKE LG&E KU Licensed energy suppliers (a) $ 584 $ — $ — $ — $ — Residential 804 408 396 197 199 Commercial 325 98 227 124 103 Industrial 155 13 142 44 98 Other (b) 105 13 68 31 37 Wholesale - municipal 30 — 30 — 30 Wholesale - other (c) 34 — 34 36 16 Transmission 105 105 — — — Revenues from Contracts with Customers $ 2,142 $ 637 $ 897 $ 432 $ 483 (a) Represents customers of WPD. (b) Primarily includes revenues from pole attachments, street lighting and other public authorities. (c) Includes wholesale power and transmission revenues. LG&E and KU amounts include intercompany power sales and transmission revenues, which are eliminated upon consolidation at LKE. Contract receivables from customers are primarily included in "Account receivable - Customer" and "Unbilled revenues" on the Balance Sheets. The following table shows the accounts receivable balances that were impaired for the period ended March 31, 2018 . Three Months PPL $ 10 PPL Electric 7 LKE 2 LG&E 1 KU 1 The following table shows the balances and certain activity of contract liabilities resulting from contracts with customers. PPL PPL Electric LKE LG&E KU Contract liabilities as of December 31, 2017 $ 29 $ 19 $ 8 $ 4 $ 4 Contract liabilities as of March 31, 2018 20 11 7 3 4 Revenue recognized during the period that was included in the opening contract liability balance 17 8 8 4 4 Contract liabilities result from recording contractual billings in advance for customer attachments to the Registrants' infrastructure and payments received in excess of revenues earned to date. Advanced billings for customer attachments are recognized as revenue ratably over the billing period. Payments received in excess of revenues earned to date are recognized as revenue as electricity is delivered in subsequent periods.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	5. Earnings Per Share (PPL) Basic EPS is computed by dividing income available to PPL common shareowners by the weighted-average number of common shares outstanding during the applicable period. Diluted EPS is computed by dividing income available to PPL common shareowners by the weighted-average number of common shares outstanding, increased by incremental shares that would be outstanding if potentially dilutive non-participating securities were converted to common shares as calculated using the Treasury Stock Method. Incremental non-participating securities that have a dilutive impact are detailed in the table below. Reconciliations of the amounts of income and shares of PPL common stock (in thousands) for the periods ended March 31 used in the EPS calculation are: Three Months 2018 2017 Income (Numerator) Net income $ 452 $ 403 Less amounts allocated to participating securities 1 1 Net income available to PPL common shareowners - Basic and Diluted $ 451 $ 402 Shares of Common Stock (Denominator) Weighted-average shares - Basic EPS 694,514 680,882 Add incremental non-participating securities: Share-based payment awards 808 2,202 Weighted-average shares - Diluted EPS 695,322 683,084 Three Months 2018 2017 Basic EPS Net Income available to PPL common shareowners $ 0.65 $ 0.59 Diluted EPS Net Income available to PPL common shareowners $ 0.65 $ 0.59 For the periods ended March 31 , PPL issued common stock related to stock-based compensation plans and the DRIP as follows (in thousands): Three Months 2018 2017 Stock-based compensation plans (a) 476 887 DRIP 485 445 (a) Includes stock options exercised, vesting of performance units, vesting of restricted stock units and conversion of stock units granted to directors. See Note 8 for additional information on common stock issued under the ATM Program. For the periods ended March 31 , the following shares (in thousands) were excluded from the computations of diluted EPS because the effect would have been antidilutive. Three Months 2018 2017 Stock options 230 696 Restricted stock units 20 —

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	6. Income Taxes Reconciliations of income taxes for the periods ended March 31 are as follows. (PPL) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 119 $ 186 Increase (decrease) due to: State income taxes, net of federal income tax benefit 15 13 Valuation allowance adjustments 7 5 Impact of lower U.K. income tax rates relative to U.S. income tax rates (a) (7 ) (48 ) U.S. income tax on foreign earnings - net of foreign tax credit (a) (b) 1 (9 ) Impact of the U.K. Finance Acts (1 ) (3 ) Depreciation and other items not normalized (a) (12 ) (3 ) Interest benefit on U.K. financing entities (5 ) (4 ) Stock-based compensation 1 (3 ) Other (1 ) (5 ) Total increase (decrease) (2 ) (57 ) Total income taxes $ 117 $ 129 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018. (b) Lower income taxes in 2017 primarily due to the tax benefit of accelerated pension contributions made in the first quarter of 2017. The related tax benefit was recognized over the annual period as a result of utilizing an estimated annual effective tax rate. (PPL Electric) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 41 $ 44 Increase (decrease) due to: State income taxes, net of federal income tax benefit 15 8 Depreciation and other items not normalized (a) (7 ) (2 ) Stock-based compensation — (2 ) Total increase (decrease) 8 4 Total income taxes $ 49 $ 48 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018. (LKE) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 38 $ 58 Increase (decrease) due to: State income taxes, net of federal income tax benefit 8 6 Amortization of excess deferred income taxes (a) (5 ) — Other (2 ) (1 ) Total increase (decrease) 1 5 Total income taxes $ 39 $ 63 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018. (LG&E) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 20 $ 30 Increase (decrease) due to: State income taxes, net of federal income tax benefit 4 3 Amortization of excess deferred income taxes (a) (2 ) — Other (1 ) — Total increase (decrease) 1 3 Total income taxes $ 21 $ 33 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018. (KU) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 23 $ 36 Increase (decrease) due to: State income taxes, net of federal income tax benefit 5 4 Amortization of excess deferred income taxes (a) (3 ) — Other (1 ) (1 ) Total increase (decrease) 1 3 Total income taxes $ 24 $ 39 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018. Kentucky Tax Reform (All Registrants) On April 14, 2018, the Kentucky House of Representatives and Kentucky Senate passed House Bill 487 (HB 487). HB 487 provides for significant changes to the Kentucky tax code including (1) adopting mandatory combined reporting for corporate members of unitary business groups for taxable years beginning on or after January 1, 2019 (members of a unitary business group may make an eight-year binding election to file consolidated corporate income tax returns with all members of their federal affiliated group) and (2) a reduction in the Kentucky corporate income tax rate from 6% to 5% for taxable years beginning after December 31, 2017. HB 487 became law on April 27, 2018. LKE continues to evaluate the impacts of Kentucky tax reform, but expects to incur a deferred tax charge of approximately $9 million in the second quarter of 2018 associated with the remeasurement of accumulated deferred income tax balances. As indicated in Note 1 in the Registrants' 2017 Form 10-K, LG&E’s and KU’s accounting for income taxes is impacted by rate regulation. Therefore, reductions in accumulated deferred income tax balances due to the reduction in the Kentucky corporate income tax rate to 5% under the provisions of HB 487 may result in amounts previously collected from utility customers for these deferred taxes to be refundable to such customers over a period of time. LG&E and KU currently estimate the impact of the reduced tax rate, related to the remeasurement of deferred income taxes, to be an increase in regulatory liabilities of $16 million and $19 million. LG&E and KU continue to evaluate other impacts of Kentucky tax reform along with the associated regulatory considerations. PPL is evaluating the impact, if any, of unitary or elective consolidated income tax reporting on all its Registrants.

Utility Rate Regulation

Utility Rate Regulation	3 Months Ended
	Mar. 31, 2018
Regulated Operations [Abstract]
Utility Rate Regulation	7. Utility Rate Regulation (All Registrants) The following table provides information about the regulatory assets and liabilities of cost-based rate-regulated utility operations. PPL PPL Electric March 31, December 31, March 31, December 31, Current Regulatory Assets: Environmental cost recovery $ — $ 5 $ — $ — Generation formula rate 2 6 — — Smart meter rider 15 15 15 15 Plant outage costs 6 3 — — Other 5 5 1 1 Total current regulatory assets (a) $ 28 $ 34 $ 16 $ 16 Noncurrent Regulatory Assets: Defined benefit plans $ 866 $ 880 $ 496 $ 504 Taxes recoverable through future rates 3 3 3 3 Storm costs (b) 47 33 17 — Unamortized loss on debt 51 54 27 29 Interest rate swaps 22 26 — — Terminated interest rate swaps 91 92 — — Accumulated cost of removal of utility plant 176 173 176 173 AROs 247 234 — — Act 129 compliance rider 7 — 7 — Other 9 9 — — Total noncurrent regulatory assets $ 1,519 $ 1,504 $ 726 $ 709 PPL PPL Electric March 31, December 31, March 31, December 31, Current Regulatory Liabilities: Generation supply charge $ 33 $ 34 $ 33 $ 34 Transmission service charge 16 9 16 9 Environmental cost recovery 18 1 — — Universal service rider 24 26 24 26 Transmission formula rate 10 9 10 9 Fuel adjustment clause 2 3 — — TCJA bill credit (c) 34 — — — Storm damage expense rider 12 8 12 8 Other 9 5 — — Total current regulatory liabilities $ 158 $ 95 $ 95 $ 86 Noncurrent Regulatory Liabilities: Accumulated cost of removal of utility plant $ 677 $ 677 $ — $ — Power purchase agreement - OVEC (d) 66 68 — — Net deferred taxes (e) 1,839 1,853 660 668 Defined benefit plans 28 27 — — Terminated interest rate swaps 74 74 — — Other 5 5 2 — Total noncurrent regulatory liabilities $ 2,689 $ 2,704 $ 662 $ 668 LKE LG&E KU March 31, December 31, March 31, December 31, March 31, December 31, Current Regulatory Assets: Environmental cost recovery $ — $ 5 $ — $ 5 $ — $ — Generation formula rate 2 6 — — 2 6 Plant outage costs 6 3 6 3 — — Other 4 4 4 4 — — Total current regulatory assets $ 12 $ 18 $ 10 $ 12 $ 2 $ 6 Noncurrent Regulatory Assets: Defined benefit plans $ 370 $ 376 $ 230 $ 234 $ 140 $ 142 Storm costs 30 33 16 18 14 15 Unamortized loss on debt 24 25 15 16 9 9 Interest rate swaps 22 26 22 26 — — Terminated interest rate swaps 91 92 53 54 38 38 AROs 247 234 67 61 180 173 Other 9 9 3 2 6 7 Total noncurrent regulatory assets $ 793 $ 795 $ 406 $ 411 $ 387 $ 384 LKE LG&E KU March 31, December 31, March 31, December 31, March 31, December 31, Current Regulatory Liabilities: Environmental cost recovery $ 18 $ 1 $ 7 $ — $ 11 $ 1 Fuel adjustment clause 2 3 — — 2 3 Gas line tracker 2 3 2 3 — — TCJA bill credit (c) 34 — 16 — 18 — Other 7 2 4 — 3 2 Total current regulatory liabilities $ 63 $ 9 $ 29 $ 3 $ 34 $ 6 Noncurrent Regulatory Liabilities: Accumulated cost of removal of utility plant $ 677 $ 677 $ 280 $ 282 $ 397 395 Power purchase agreement - OVEC (d) 66 68 46 47 20 21 Net deferred taxes (e) 1,179 1,185 549 552 630 633 Defined benefit plans 28 27 — — 28 27 Terminated interest rate swaps 74 74 37 37 37 37 Other 3 5 — 1 3 4 Total noncurrent regulatory liabilities $ 2,027 $ 2,036 $ 912 $ 919 $ 1,115 $ 1,117 (a) For PPL, these amounts are included in "Other current assets" on the Balance Sheets. (b) Storm costs incurred in PPL Electric's territory from a March 2018 storm will be amortized from 2019 through 2021. (c) Relates to estimated amounts owed to customers as a result of the reduced U.S. federal corporate income tax rate as enacted by the TCJA, effective January 1, 2018, not yet reflected in customer rates. (d) This liability was recorded as an offset to an intangible asset that was recorded at fair value upon the acquisition of LKE by PPL. (e) Primarily relates to excess deferred taxes recorded as a result of the TCJA, which reduced the U.S. federal corporate income tax rate effective January 1, 2018, requiring deferred tax balances and the associated regulatory liabilities to be remeasured as of December 31, 2017. Regulatory Matters Kentucky Activities (PPL, LKE, LG&E and KU) CPCN Filing On January 10, 2018, LG&E and KU filed an application for a CPCN with the KPSC requesting approval to implement Advanced Metering Systems across their Kentucky service territories, including gas operations for LG&E. The full deployment is expected to be completed in 2021 with estimated capital costs of $ 155 million and $ 104 million for KU and LG&E electric service and $ 62 million for LG&E gas service. The full Advanced Metering Systems deployment is expected to result in incremental operation and maintenance costs during the deployment phase of $ 17 million and $ 11 million for KU and LG&E electric service and $ 3 million for LG&E gas service. TCJA Impact on LG&E and KU Rates On December 21, 2017, Kentucky Industrial Utility Customers, Inc. submitted a complaint with the KPSC against LG&E and KU, as well as other utility companies in Kentucky, alleging that their respective rates would no longer be fair, just and reasonable following the enactment of the TCJA reducing the federal corporate tax rate from 35% to 21%. The complaint requested the KPSC to issue an order requiring LG&E and KU to begin deferring, as of January 1, 2018, the revenue requirement effect of all income tax expense savings resulting from the federal corporate income tax reduction, including the amortization of excess deferred income taxes by recording those savings in a regulatory liability account and establishing a process by which the federal corporate income tax savings will be passed back to customers. On January 29, 2018, LG&E, KU, Kentucky Industrial Utility Customers, Inc. and the Office of the Attorney General reached a settlement agreement to commence returning savings related to the TCJA to their customers. The savings will be distributed through their ECR, DSM and LG&E's GLT rate mechanisms beginning in March 2018 and through a new bill credit mechanism from April 1, 2018 through April 30, 2019. The estimated impact of the rate reduction represents approximately $91 million in KU electricity revenues ( $70 million through the new bill credit and $21 million through existing rate mechanisms), $69 million in LG&E electricity revenues ( $49 million through the new bill credit and $20 million through existing rate mechanisms) and $17 million in LG&E gas revenues (substantially all through the new bill credit) for the period January 2018 through April 2019. Ongoing tax savings are expected to also be addressed in LG&E's and KU's next Kentucky base rate case. LG&E and KU have indicated their intent to file an application for base rate changes during 2018 to be effective during spring 2019. On March 20, 2018, the KPSC issued an order approving, with certain modifications, the settlement agreement reached between LG&E, KU, Kentucky Industrial Utility Customers, Inc. and the Office of the Attorney General. The KPSC estimates that, pursuant to its modifications, electricity revenues would incorporate reductions of approximately $108 million for KU ( $87 million through the new bill credit and $21 million through existing rate mechanisms) and $79 million for LG&E ( $59 million through the new bill credit and $20 million through existing rate mechanisms). This represents $27 million ( $17 million at KU and $10 million at LG&E) in additional reductions from the amounts proposed by the settlement. The KPSC's modifications to the settlement include certain changes in assumptions or inputs used in assessing tax reform or calculating LG&E's and KU's electricity rates. LG&E gas rate reductions were not modified significantly from the amount included in the settlement agreement. On March 26, 2018, LG&E and KU filed a petition for reconsideration and request for hearing with the KPSC, taking exception to the KPSC's modifications and the process, and also requested certain relief from implementing the amounts represented by the additional reductions until the matter is fully resolved. On March 28, 2018, the Office of the Attorney General filed a response to the petition and gave notice of its withdrawal from the settlement agreement. On March 28, 2018, the KPSC issued an Order granting LG&E's and KU's request for reconsideration and amending its March 20, 2018 Order by suspending the approved rates, allowing LG&E and KU, on an interim basis, to return savings related to the TCJA at the rates agreed to in the January 29, 2018 settlement. On March 30, 2018, following receipt of the Attorney General's response, the KPSC issued an Order amending its March 28, 2018 Order to allow the parties to raise any relevant issue related to the TCJA. A hearing on this matter is scheduled for May 24, 2018. LG&E and KU cannot predict the outcome of these proceedings . Additionally, on January 8, 2018, the VSCC ordered KU, as well as other utilities in Virginia, to accrue regulatory liabilities reflecting the Virginia jurisdictional revenue requirement impacts of the reduced federal corporate tax rate. On March 22, 2018, KU reached a settlement agreement regarding its ongoing rate case in Virginia. New rates, inclusive of TCJA impacts, will be effective June 1, 2018. The settlement also stipulates that actual tax savings for the five month period prior to new rates taking effect will be addressed through KU's annual information filing for calendar year 2018. The settlement agreement is subject to review and approval by the VSCC. On April 16, 2018, the hearing examiner issued a report recommending that the VSCC approve the settlement agreement. The TCJA and rate case are not expected to have a significant impact on KU's financial condition or results of operations related to Virginia. On March 15, 2018, the FERC issued a Notice of Inquiry seeking information on whether and how it should address changes relating to accumulated deferred income taxes and bonus depreciation resulting from passage of the TCJA on FERC-jurisdictional rates. LG&E and KU have not made any submission in response to the Notice of Inquiry, but do not anticipate the impact of the TCJA related to their FERC-jurisdictional rates to be significant. Gas Franchise (LKE and LG&E) LG&E’s gas franchise agreement for the Louisville/Jefferson County service area expired in March 2016. In August 2016, LG&E and Louisville/Jefferson County entered into a revised franchise agreement with a 5 -year term (with renewal options). The franchise fee may be modified at Louisville/Jefferson County's election upon 60 days' notice. However, any franchise fee is capped at 3% of gross receipts for natural gas service within the franchise area. The agreement further provides that if the KPSC determines that the franchise fee should be recovered from LG&E's Louisville/Jefferson county customers in the franchise areas as a separate line item on their bill, the franchise fee will revert to zero . In August 2016, LG&E filed an application requesting the KPSC to review and rule upon the recoverability of the franchise fee. On March 14, 2018, the KPSC issued an order authorizing the franchise fee to be recovered only from LG&E's Louisville/Jefferson County customers in the franchise area. As a result, the franchise fee will continue to be zero in accordance with the terms of the August 2016, 5 -year gas franchise agreement. (PPL and PPL Electric) Pennsylvania Activities TCJA Impact on PPL Electric Rates The PUC issued a Secretarial Letter on February 12, 2018 regarding the TCJA, requesting certain information from regulated utilities and inviting comment from interested parties on potential revision to customer rates as a result of enactment of the TCJA. PPL Electric submitted its response to the Secretarial Letter on March 9, 2018. On March 15, 2018, the PUC issued a Temporary Rates Order which will remain in effect for up to six months and may be extended for an additional six months. The PUC anticipates that the process to determine the manner in which rates will be adjusted in response to the TCJA will require further review and analysis of the responses to data requests, financial information and public comments submitted in response to the Secretarial Letter. For the period ended March 31, 2018, PPL Electric has not recorded an accrual with respect to any potential rate adjustment due to the adoption of the TCJA, as PPL Electric believes it is not probable that a loss has been incurred. Under applicable law, it is reasonably possible that the PUC could seek to adjust rates as of March 15, 2018, the date of the Temporary Rates Order. In that case, PPL Electric's estimated maximum loss exposure would be the excess amounts collected in customer rates related to applicable federal income taxes since the date of the Temporary Rates Order, which amount is immaterial as of March 31, 2018. On March 15, 2018, the FERC issued a Notice of Inquiry seeking information on whether and how it should address changes to FERC-jurisdictional rates relating to accumulated deferred income taxes and bonus depreciation resulting from passage of the TCJA. In a news release issued the same day, the FERC acknowledged that many transmission rates automatically adjust with changes in the tax rates and the adjustments for much of the industry are already taking place. PPL Electric has not made any submission in response to the Notice of Inquiry. On March 16, 2018, PPL Electric filed a waiver pursuant to Rule 207(a)(5) of the Rules of Practice and Procedure of the Federal Energy Regulatory Commission with the FERC to request the incorporation of the changes to the federal income tax rate in its transmission formula rate commencing on June 1, 2018 rather than allowing the TCJA reduction in the federal income tax rate to be initially incorporated in PPL Electric's June 1, 2019 transmission formula rate. The waiver was approved on April 23, 2018 and PPL Electric submitted its transmission formula rate, which was inclusive of the federal income tax rate as set by the TCJA, on April 27, 2018. Other Purchase of Receivables Program (PPL and PPL Electric) In accordance with a PUC-approved purchase of accounts receivable program, PPL Electric purchases certain accounts receivable from alternative electricity suppliers at a discount, which reflects a provision for uncollectible accounts. The alternative electricity suppliers have no continuing involvement or interest in the purchased accounts receivable. Accounts receivable that are acquired are initially recorded at fair value on the date of acquisition. During the three months ended March 31, 2018 and 2017, PPL Electric purchased $376 million and $356 million of accounts receivable from alternate suppliers.

Financing Activities

Financing Activities	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Financing Activities	8. Financing Activities Credit Arrangements and Short-term Debt (All Registrants) The Registrants maintain credit facilities to enhance liquidity, provide credit support and act as a backstop to commercial paper programs. For reporting purposes, on a consolidated basis, the credit facilities and commercial paper programs of PPL Electric, LKE, LG&E and KU also apply to PPL and the credit facilities and commercial paper programs of LG&E and KU also apply to LKE. The amounts borrowed below are recorded as "Short-term debt" on the Balance Sheets except for borrowings under LG&E's term loan agreement, which are reflected in "Long-term debt" on the Balance Sheets. The following credit facilities were in place at: March 31, 2018 December 31, 2017 Expiration Date Capacity Borrowed Letters of Credit and Commercial Paper Issued Unused Capacity Borrowed Letters of Credit and Commercial Paper Issued PPL U.K. WPD plc Syndicated Credit Facility (a) Jan. 2022 £ 210 £ 145 £ — £ 67 £ 148 £ — Term Loan Facility (b) Dec. 2018 130 130 — — — — WPD (South West) Syndicated Credit Facility July 2021 245 — — 245 — — WPD (East Midlands) Syndicated Credit Facility (c) July 2021 300 157 — 143 180 — WPD (West Midlands) Syndicated Credit Facility (d) July 2021 300 65 — 235 120 — Uncommitted Credit Facilities 130 — 4 126 — 4 Total U.K. Credit Facilities (e) £ 1,315 £ 497 £ 4 £ 816 £ 448 £ 4 U.S. PPL Capital Funding Syndicated Credit Facility Jan. 2023 $ 950 $ — $ 345 $ 605 $ — $ 230 Syndicated Credit Facility Nov. 2018 300 — — 300 — — Bilateral Credit Facility Mar. 2019 100 — 24 76 — 18 Total PPL Capital Funding Credit Facilities $ 1,350 $ — $ 369 $ 981 $ — $ 248 PPL Electric Syndicated Credit Facility Jan. 2023 $ 650 $ — $ 214 $ 436 $ — $ 1 LKE Syndicated Credit Facility Oct. 2018 $ 75 $ — $ — $ 75 $ — $ — LG&E Syndicated Credit Facility Jan. 2023 $ 500 $ — $ 137 $ 363 $ — $ 199 Term Loan Credit Facility Oct. 2019 200 200 — — 100 — Total LG&E Credit Facilities $ 700 $ 200 $ 137 $ 363 $ 100 $ 199 KU Syndicated Credit Facility Jan. 2023 $ 400 $ — $ 78 $ 322 $ — $ 45 Letter of Credit Facility Oct. 2020 198 — 198 — — 198 Total KU Credit Facilities $ 598 $ — $ 276 $ 322 $ — $ 243 (a) The amounts borrowed at March 31, 2018 and December 31, 2017 were USD-denominated borrowings of $200 million for both periods, which bore interest at 2.47% and 2.17% . The unused capacity reflects the amount borrowed in GBP of £143 million as of the date borrowed. (b) The amount borrowed at March 31, 2018 was a GBP-denominated borrowing which equated to $179 million and bore interest at 1.77% . (c) The amounts borrowed at March 31, 2018 and December 31, 2017 were GBP-denominated borrowings which equated to $216 million and $244 million and bore interest at 0.90% and 0.89% . (d) The amounts borrowed at March 31, 2018 and December 31, 2017 were GBP-denominated borrowings which equated to $89 million and $162 million and bore interest at 0.90% and 0.89% . (e) At March 31, 2018 , the unused capacity under the U.K. credit facilities was $1.1 billion . In January 2018, LG&E borrowed the remaining $100 million available under its $200 million term loan facility. The proceeds were used to repay short-term debt and for general corporate purposes. PPL, PPL Electric, LG&E and KU maintain commercial paper programs to provide an additional financing source to fund short-term liquidity needs, as necessary. Commercial paper issuances, included in "Short-term debt" on the Balance Sheets, are supported by the respective Registrant's Syndicated Credit Facility. The following commercial paper programs were in place at: March 31, 2018 December 31, 2017 Weighted - Average Interest Rate Capacity Commercial Paper Issuances Unused Capacity Weighted - Average Interest Rate Commercial Paper Issuances PPL Capital Funding 2.44% $ 1,000 $ 345 $ 655 1.64% $ 230 PPL Electric 2.42% 650 213 437 — LG&E 2.23% 350 137 213 1.83% 199 KU 2.35% 350 78 272 1.97% 45 Total $ 2,350 $ 773 $ 1,577 $ 474 (PPL Electric, LKE, and LG&E) See Note 11 for discussion of intercompany borrowings. Long-term Debt (PPL) In March 2018, WPD (South Wales) issued £30 million of 0.01% Index-linked Senior Notes due 2036 . WPD (South Wales) received proceeds of £31 million , which equated to $44 million at the time of issuance, net of fees and including a premium. The principal amount of the notes is adjusted based on changes in a specified index, as detailed in the terms of the related indenture. The proceeds were used for general corporate purposes. (PPL, LKE and LG&E) In March 2018, the County of Trimble, Kentucky remarketed $28 million of Pollution Control Revenue Bonds, 2001 Series A (Louisville Gas and Electric Company Project) due 2026 previously issued on behalf of LG&E. The bonds were remarketed at a long-term rate and will bear interest at 2.30% through their mandatory purchase date of September 1, 2021 . In May 2018, the County of Trimble, Kentucky remarketed $35 million of Pollution Control Revenue Bonds, 2001 Series B (Louisville Gas and Electric Company Project) due 2027 previously issued on behalf of LG&E. The bonds were remarketed at a long-term rate and will bear interest at 2.55% through their mandatory purchase date of May 3, 2021 . In May 2018, the County of Jefferson, Kentucky remarketed $35 million of Pollution Control Revenue Bonds, 2001 Series B (Louisville Gas and Electric Company Project) due 2027 previously issued on behalf of LG&E. The bonds were remarketed at a long-term rate and will bear interest at 2.55% through their mandatory purchase date of May 3, 2021 . (LKE) In May 2018, LKE borrowed $250 million from a PPL affiliate through the issuance of a 4% ten-year note due 2028 . The proceeds were used to repay its outstanding notes payable with a PPL Energy Funding subsidiary. See Note 11 for more information related to intercompany borrowings. (PPL) ATM Program In February 2018, PPL entered into a distribution agreement, pursuant to which PPL may sell, from time to time, up to an aggregate of $1.0 billion of its common stock. The compensation paid to the selling agents by PPL may be up to 2% of the gross offering proceeds of the shares sold with respect to the equity distribution agreement. PPL issued 3.0 million shares of common stock and received gross proceeds of $85 million for the three months ended March 31, 2018 . Distributions In February 2018 , PPL declared a quarterly common stock dividend, payable April 2, 2018 , of 41.0 cents per share (equivalent to $1.64 per annum). Future dividends, declared at the discretion of the Board of Directors, will depend upon future earnings, cash flows, financial and legal requirements and other factors.

Defined Benefits

Defined Benefits	3 Months Ended
	Mar. 31, 2018
Retirement Benefits [Abstract]
Defined Benefits	9. Defined Benefits (PPL, LKE and LG&E) Certain net periodic defined benefit costs are applied to accounts that are further distributed among capital, expense and regulatory assets, including certain costs allocated to applicable subsidiaries for plans sponsored by PPL Services and LKE. Following are the net periodic defined benefit costs (credits) of the plans sponsored by PPL and its subsidiaries, LKE and its subsidiaries, and LG&E for the periods ended March 31 : Pension Benefits Three Months U.S. U.K. 2018 2017 2018 2017 PPL Service cost $ 16 $ 17 $ 21 $ 19 Interest cost 39 42 47 43 Expected return on plan assets (62 ) (57 ) (150 ) (125 ) Amortization of: Prior service cost 2 2 — — Actuarial loss 22 20 39 35 Net periodic defined benefit costs (credits) before settlements and special termination benefits 17 24 (43 ) (28 ) Special termination benefits (a) — 2 — — Net periodic defined benefit costs (credits) $ 17 $ 26 $ (43 ) $ (28 ) (a) Enhanced pension benefits offered to certain PPL Electric bargaining unit employees under a one-time voluntary retirement window offered as part of the new five year IBEW contract ratified in March 2017. Pension Benefits Three Months 2018 2017 LKE Service cost $ 7 $ 7 Interest cost 16 16 Expected return on plan assets (26 ) (22 ) Amortization of: Prior service cost 2 2 Actuarial loss (a) 10 11 Net periodic defined benefit costs $ 9 $ 14 (a) As a result of treatment approved by the KPSC, the difference between actuarial loss calculated in accordance with LKE's accounting policy and actuarial loss calculated using a 15 -year amortization period was $4 million and $5 million for the three months ended March 31, 2018 and 2017. This difference is recorded as a regulatory asset. Pension Benefits Three Months 2018 2017 LG&E Interest cost $ 3 $ 3 Expected return on plan assets (5 ) (5 ) Amortization of: Prior service cost 1 1 Actuarial loss (a) 2 3 Net periodic defined benefit costs $ 1 $ 2 (a) As a result of treatment approved by the KPSC, the difference between actuarial loss calculated in accordance with LG&E's accounting policy and actuarial loss calculated using a 15 -year amortization period was $1 million for the three months ended March 31, 2018 and 2017. This difference is recorded as a regulatory asset. Other Postretirement Benefits Three Months 2018 2017 PPL Service cost $ 1 $ 2 Interest cost 3 6 Expected return on plan assets (4 ) (6 ) Amortization of prior service cost (1 ) — Net periodic defined benefit costs (credits) $ (1 ) $ 2 LKE Service cost $ 1 $ 1 Interest cost 2 2 Expected return on plan assets (2 ) (1 ) Net periodic defined benefit costs $ 1 $ 2 (PPL Electric, LG&E and KU) In addition to the specific plan it sponsors, LG&E is allocated costs of defined benefit plans sponsored by LKE. PPL Electric and KU do not directly sponsor any defined benefit plans. PPL Electric is allocated costs of defined benefit plans sponsored by PPL Services and KU is allocated costs of defined benefit plans sponsored by LKE. LG&E and KU are also allocated costs of defined benefit plans from LKS for defined benefit plans sponsored by LKE. See Note 11 for additional information on costs allocated to LG&E and KU from LKS. These allocations are based on participation in those plans, which management believes are reasonable. For the periods ended March 31 , PPL Services allocated the following net periodic defined benefit costs to PPL Electric, and LKE allocated the following net periodic defined benefit costs to LG&E and KU: Three Months 2018 2017 PPL Electric $ 4 $ 8 LG&E 2 3 KU 1 4 (All Registrants) The non-service cost components of net periodic defined benefit costs (credits) (interest cost, expected return on plan assets, amortization of prior service cost and amortization of actuarial loss) are presented in "Other Income (Expense) - net" on the Statements of Income. See Note 12 for details.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	10. Commitments and Contingencies Legal Matters (All Registrants) PPL and its subsidiaries are involved in legal proceedings, claims and litigation in the ordinary course of business. PPL and its subsidiaries cannot predict the outcome of such matters, or whether such matters may result in material liabilities, unless otherwise noted. Cane Run Environmental Claims (PPL, LKE and LG&E) In December 2013, six residents, on behalf of themselves and others similarly situated, filed a class action complaint against LG&E and PPL in the U.S. District Court for the Western District of Kentucky alleging violations of the Clean Air Act, RCRA, and common law claims of nuisance, trespass and negligence. These plaintiffs seek injunctive relief and civil penalties, plus costs and attorney fees, for the alleged statutory violations. Under the common law claims, these plaintiffs seek monetary compensation and punitive damages for property damage and diminished property values for a class consisting of residents within four miles of the Cane Run plant, which had three coal-fired units retired in 2015. In their individual capacities, these plaintiffs sought compensation for alleged adverse health effects. In July 2014, the court dismissed the RCRA claims and all but one Clean Air Act claim, but declined to dismiss the common law tort claims. In November 2016, the plaintiffs filed an amended complaint removing the personal injury claims and removing certain previously named plaintiffs. In February 2017, the District Court issued an order dismissing PPL as a defendant and dismissing the final federal claim against LG&E. On April 13, 2017, the federal District Court issued an order declining to exercise supplemental jurisdiction on the state law claims and dismissed the case in its entirety. On June 16, 2017, the plaintiffs filed a class action complaint in Jefferson Circuit Court, Kentucky, against LG&E alleging state law nuisance, negligence and trespass tort claims. The plaintiffs seek compensatory and punitive damages for alleged property damage due to purported plant emissions on behalf of a class of residents within one to three miles of the plant. Proceedings are currently underway regarding potential class certification, for which a decision may occur in late 2018 or in 2019. PPL, LKE and LG&E cannot predict the outcome of this matter and an estimate or range of possible losses cannot be determined. E.W. Brown Environmental Claims ( PPL, LKE and KU) On July 12, 2017, the Kentucky Waterways Alliance and the Sierra Club filed a citizen suit complaint against KU in the U.S. District Court for the Eastern District of Kentucky alleging discharges at the E.W. Brown plant in violation of the Clean Water Act and the plant’s water discharge permit and alleging contamination that may present an imminent and substantial endangerment in violation of the RCRA. The plaintiffs’ suit relates to prior notices of intent to file a citizen suit submitted in October and November 2015 and October 2016. These plaintiffs sought injunctive relief ordering KU to take all actions necessary to comply with the Clean Water Act and RCRA, including ceasing the discharges in question, abating effects associated with prior discharges and eliminating the alleged imminent and substantial endangerment. These plaintiffs also sought assessment of civil penalties and an award of litigation costs and attorney fees. On December 28, 2017 the U.S. District Court for the Eastern District of Kentucky issued an order dismissing the Clean Water Act and RCRA complaints against KU in their entirety. On January 26, 2018, the plaintiffs appealed the dismissal order to the U.S. Court of Appeals for the Sixth Circuit. KU is undertaking extensive remedial measures at the E.W. Brown plant including closure of the former ash pond, implementation of a groundwater remedial action plan, and performance of a corrective action plan including aquatic study of adjacent surface waters and risk assessment. PPL, LKE and KU cannot predict the outcome of these matters and an estimate or range of possible losses cannot be determined. Regulatory Issues ( All Registrants) See Note 7 for information on regulatory matters related to utility rate regulation. Electricity - Reliability Standards The NERC is responsible for establishing and enforcing mandatory reliability standards (Reliability Standards) regarding the bulk electric system in North America. The FERC oversees this process and independently enforces the Reliability Standards. The Reliability Standards have the force and effect of law and apply to certain users of the bulk electric system, including electric utility companies, generators and marketers. Under the Federal Power Act, the FERC may assess civil penalties for certain violations. PPL Electric, LG&E and KU monitor their compliance with the Reliability Standards and self-report or self-log potential violations of applicable reliability requirements whenever identified, and submit accompanying mitigation plans, as required. The resolution of a small number of potential violations is pending. Penalties incurred to date have not been significant. Any Regional Reliability Entity (including RFC or SERC) determination concerning the resolution of violations of the Reliability Standards remains subject to the approval of the NERC and the FERC. In the course of implementing their programs to ensure compliance with the Reliability Standards by those PPL affiliates subject to the standards, certain other instances of potential non-compliance may be identified from time to time. The Registrants cannot predict the outcome of these matters, and an estimate or range of possible losses cannot be determined. Environmental Matters (All Registrants) Due to the environmental issues discussed below or other environmental matters, it may be necessary for the Registrants to modify, curtail, replace or cease operation of certain facilities or performance of certain operations to comply with statutes, regulations and other requirements of regulatory bodies or courts. In addition, legal challenges to new environmental permits or rules add to the uncertainty of estimating the future cost of these permits and rules. Finally, the regulatory reviews specified in the President's March 2017 Executive Order (the March 2017 Executive Order) promoting energy independence and economic growth could result in future regulatory changes and additional uncertainty. WPD's distribution businesses are subject to certain statutory and regulatory environmental requirements. It may be necessary for WPD to incur significant compliance costs, which costs may be recoverable through rates subject to the approval of Ofgem. PPL believes that WPD has taken and continues to take measures to comply with all applicable environmental laws and regulations. LG&E and KU are entitled to recover, through the ECR mechanism, certain costs of complying with the Clean Air Act, as amended, and those federal, state or local environmental requirements applicable to coal combustion wastes and by-products from facilities that generate electricity from coal in accordance with approved compliance plans. Costs not covered by the ECR mechanism for LG&E and KU and all such costs for PPL Electric are subject to rate recovery before the companies' respective state regulatory authorities, or the FERC, if applicable. Because neither WPD nor PPL Electric owns any generating plants, their exposure to related environmental compliance costs is reduced. PPL, PPL Electric, LKE, LG&E and KU can provide no assurances as to the ultimate outcome of future environmental or rate proceedings before regulatory authorities. Air (PPL, LKE, LG&E and KU) NAAQS The Clean Air Act, which regulates air pollutants from mobile and stationary sources in the United States, has a significant impact on the operation of fossil fuel generation plants. Among other things, the Clean Air Act requires the EPA periodically to review and establish concentration levels in the ambient air for six pollutants to protect public health and welfare. The six pollutants are carbon monoxide, lead, nitrogen dioxide, ozone (contributed to by nitrogen oxide emissions), particulate matter and sulfur dioxide. The established concentration levels for these six pollutants are known as NAAQS. Under the Clean Air Act, the EPA is required to reassess the NAAQS on a five-year schedule. Federal environmental regulations of these six pollutants require states to adopt implementation plans, known as state implementation plans, which detail how the state will attain the standards that are mandated by the relevant law or regulation. Each state identifies the areas within its boundaries that meet the NAAQS (attainment areas) and those that do not (non-attainment areas), and must develop a state implementation plan both to bring non-attainment areas into compliance with the NAAQS and to maintain good air quality in attainment areas. In addition, for attainment of ozone and fine particulates standards, states in the eastern portion of the country, including Kentucky, are subject to a regional program developed by the EPA known as the Cross-State Air Pollution Rule. The NAAQS, future revisions to the NAAQS and state implementation plans, or future revisions to regional programs, may require installation of additional pollution controls, the costs of which PPL, LKE, LG&E and KU believe are subject to cost recovery. Although PPL, LKE, LG&E and KU do not anticipate significant costs to comply with these programs, changes in market or operating conditions could result in different costs than anticipated. Ozone The EPA issued the current ozone standard in October 2015. The states and the EPA are required to determine (based on ambient air monitoring data) those areas that meet the standard and those that are in non-attainment. The EPA was scheduled to designate areas as being in attainment or nonattainment of the current ozone standard by no later than October 2017 which was to be followed by further regulatory proceedings identifying compliance measures and deadlines. However, the current implementation and compliance schedule is uncertain because the EPA failed to make nonattainment designations by the applicable deadline. In addition, some industry groups have requested the EPA to defer implementation of the 2015 ozone standard, but the EPA has not yet acted on this request. Although implementation of the 2015 ozone standard could potentially require the addition of SCRs at some LG&E and KU generating units, PPL, LKE, LG&E and KU are currently unable to determine what the compliance measures and deadlines may ultimately be with respect to the new standard. States are also obligated to address interstate transport issues associated with ozone standards through the establishment of "good neighbor" state implementation plans for those states that are found to contribute significantly to another state's non-attainment. As a result of a partial consent decree addressing claims regarding federal implementation, the EPA and several states, including Kentucky, are evaluating the need for further nitrogen oxide reductions from fossil-fueled plants to address interstate impacts. Although PPL, LKE, LG&E and KU are unable to predict the outcome of ongoing and future evaluations by the EPA and the states, such evaluations could potentially result in requirements for nitrogen oxide reductions beyond those currently required under the Cross State Air Pollution Rule. Sulfur Dioxide In 2010, the EPA issued the current NAAQS for sulfur dioxide and required states to identify areas that meet those standards and areas that are in "non-attainment". In July 2013, the EPA finalized non-attainment designations for parts of the country, including part of Jefferson County in Kentucky. As a result of scrubber replacements completed by LG&E at the Mill Creek plant in 2016, all Jefferson County monitors now indicate compliance with the sulfur dioxide standards. Additionally, LG&E accepted a new sulfur dioxide emission limit to ensure continuing compliance with the NAAQS. PPL, LKE, LG&E and KU do not anticipate any further measures to achieve compliance with the new sulfur dioxide standards. Climate Change There is continuing world-wide attention focused on issues related to climate change. In June 2016, President Obama announced that the United States, Canada and Mexico established the North American Climate, Clean Energy, and Environment Partnership Plan, which specifies actions to promote clean energy, address climate change and protect the environment. The plan includes a goal to provide 50% of the energy used in North America from clean energy sources by 2025. The plan does not impose any nation-specific requirements. In December 2015, 195 nations, including the U.S., signed the Paris Agreement on Climate, which establishes a comprehensive framework for the reduction of GHG emissions from both developed and developing nations. Although the agreement does not establish binding reduction requirements, it requires each nation to prepare, communicate, and maintain GHG reduction commitments. Reductions can be achieved in a variety of ways, including energy conservation, power plant efficiency improvements, reduced utilization of coal-fired generation or replacing coal-fired generation with natural gas or renewable generation. Based on the EPA's rules issued in 2015 imposing GHG emission standards for both new and existing power plants, the U.S. committed to an initial reduction target of 26% to 28% below 2005 levels by 2025. However, on June 1, 2017, President Trump announced a plan to withdraw from the Paris Agreement and undertake negotiations to reenter the current agreement or enter a new agreement on terms more favorable to the U.S. Under the terms of the Paris Agreement, any U.S. withdrawal would not be complete until November 2020. Additionally, the March 2017 Executive Order directed the EPA to review its 2015 greenhouse gas rules for consistency with certain policy directives and suspend, revise, or rescind those rules as appropriate. The March 2017 Executive Order also directs rescission of specified guidance, directives, and prior Presidential actions regarding climate change. PPL, LKE, LG&E and KU cannot predict the outcome of such regulatory actions or the impact, if any, on plant operations, rate treatment or future capital or operating needs. The U.K. has enacted binding carbon reduction requirements that are applicable to WPD. Under the U.K. law, WPD must purchase carbon allowances to offset emissions associated with WPD's operations. The cost of these allowances is not significant and is included in WPD's current operating expenses. The EPA's Rules under Section 111 of the Clean Air Act, including the EPA's Clean Power Plan There continues to be uncertainty about the EPA's regulation of existing coal-fired power plants. In 2015 the EPA had finalized rules imposing GHG emission standards for both new and existing power plants and had proposed a federal implementation plan that would apply to any states that failed to submit an acceptable state implementation plan to reduce GHG emissions on a state-by-state basis (the 2015 EPA Rules). Following legal challenges to the 2015 EPA Rules, a stay of those rules by the U.S. Supreme Court and the March 2017 Executive Order requiring the EPA to review the 2015 EPA Rules, in October 2017, the EPA proposed to rescind the 2015 EPA Rules and, in December 2017, released an advanced notice of proposed rulemaking for a replacement (Replacement Rules) which contemplates GHG reductions based on "inside the fence" measures implemented at individual plants. The contemplated approach in the Replacement Rules is a more limited approach than that taken in the 2015 EPA Rules which had included assumed increased levels of fuel switching and renewable energy in determining the level of emission reduction required by each state. At present, the 2015 EPA Rules remain stayed and the Replacement Rules have not yet been published. In April 2014, the Kentucky General Assembly passed legislation limiting the measures that the Kentucky Energy and Environment Cabinet may consider in setting performance standards to comply with the 2015 EPA Rules, if enacted. The legislation provides that such state GHG performance standards will be based on emission reductions, efficiency measures and other improvements available at each power plant, rather than renewable energy, end-use energy efficiency, fuel switching and re-dispatch. These statutory restrictions are consistent with the EPA's notice of proposed rulemaking on the Replacement Rules. LG&E and KU are monitoring developments at the state and federal level. Until there is more clarity about the potential requirements that may be imposed under the Replacement Rules and Kentucky's implementation plan, PPL, LKE, LG&E and KU cannot predict the potential impact, if any, on plant operations, future capital or operating costs. PPL, LKE, LG&E and KU believe that the costs, which could be significant, would be subject to rate recovery. Sulfuric Acid Mist Emissions (PPL, LKE and LG&E) In June 2016, the EPA issued a notice of violation under the Clean Air Act alleging that LG&E violated applicable rules relating to sulfuric acid mist emissions at its Mill Creek plant. The notice alleges failure to install proper controls, failure to operate the facility consistent with good air pollution control practice, and causing emissions exceeding applicable requirements or constituting a nuisance or endangerment. LG&E believes it has complied with applicable regulations during the relevant time period. Discussions between the EPA and LG&E are ongoing. The parties have entered into a tolling agreement with respect to this matter through December 2018. PPL, LKE and LG&E are unable to predict the outcome of this matter or the potential impact on operations of the Mill Creek plant, including increased capital or operating costs, and potential civil penalties or remedial measures, if any. Water/Waste (PPL, LKE, LG&E and KU) CCRs In April 2015, the EPA published its final rule regulating CCRs. CCRs include fly ash, bottom ash and sulfur dioxide scrubber wastes. The rule became effective in October 2015. It imposes extensive new requirements, including location restrictions, design and operating standards, groundwater monitoring and corrective action requirements, and closure and post-closure care requirements on CCR impoundments and landfills that are located on active power plants in the United States and not closed. Under the rule, CCRs are regulated as non-hazardous under Subtitle D of RCRA and beneficial use of CCRs is allowed, with some restrictions. The rule's requirements for covered CCR impoundments and landfills include implementation of groundwater monitoring and commencement or completion of closure activities generally between three and ten years from certain triggering events. The rule requires posting of compliance documentation on a publicly accessible website. Industry groups, environmental groups, individual companies and others have filed legal challenges to the final rule, which are pending before the D.C. Circuit Court of Appeals. On March 1, 2018, the EPA proposed amendments to the CCR rule primarily relating to impoundment closure and remediation requirements. PPL, LKE, LG&E and KU are unable to predict the outcome of the proposed rulemaking or potential impacts on current LG&E and KU compliance plans, revisions to the current rule could potentially result in additional costs. In January 2017, Kentucky issued a new state rule relating to CCR matters, effective May 2017, aimed at reflecting the requirements of the federal CCR rule. In May 2017, a resident adjacent to LG&E's and KU's Trimble County plant filed a lawsuit in Franklin County, Kentucky Circuit Court against the Kentucky Energy and Environmental Cabinet and LG&E seeking to invalidate the new rule. On January 31, 2018, the state court issued an opinion invalidating certain procedural elements of the new rule but finding the substantive requirements of the new rule to be consistent with those of the federal CCR rule. This ruling was not appealed by any party to the litigation and is now final. Accordingly, LG&E and KU presently operate their facilities under continuing permits authorized via the former program and do not currently anticipate material impacts as a result of the judicial ruling. Separately, in December 2016, federal legislation was enacted that authorized the EPA to approve equally protective state programs that would operate in lieu of the CCR rule. The Kentucky Energy and Environmental Cabinet has indicated it may propose rules under such authority in the future. LG&E and KU received KPSC approval for a compliance plan providing for the closure of impoundments at the Mill Creek, Trimble County, E.W. Brown, and Ghent stations, and construction of process water management facilities at those plants. In addition to the foregoing measures required for compliance with the federal CCR rule, KU also received KPSC approval for its plans to close impoundments at the retired Green River, Pineville and Tyrone plants to comply with applicable state law. On January 26, 2018, KU filed an application requesting a CPCN and approval of amendments to the second phase of its compliance plan for the landfill at the E.W. Brown station. A hearing related to this matter is set for June 21, 2018. KU is unable to predict the outcome of this matter but does not anticipate that it will have a material effect on its financial condition or results of operations. In connection with the final CCR rule, LG&E and KU recorded adjustments to existing AROs beginning in 2015 and continue to record adjustments as required. See Note 16 below and Note 19 in the Registrants' 2017 Form 10-K for additional information. Further changes to AROs, current capital plans or operating costs may be required as estimates are refined based on closure developments, groundwater monitoring results, and regulatory or legal proceedings. Costs relating to this rule are subject to rate recovery. Clean Water Act Regulations under the federal Clean Water Act dictate permitting and mitigation requirements for facilities and construction projects in the United States. Many of those requirements relate to power plant operations, including requirements related to the treatment of pollutants in effluents prior to discharge, the temperature of effluent discharges and the location, design and construction of cooling water intake structures at generating facilities, standards intended to protect aquatic organisms that become trapped at or pulled through cooling water intake structures at generating facilities. The requirements could impose significant costs for LG&E and KU, which are subject to rate recovery. On February 20, 2018, the EPA issued a notice requesting comment on the scope of discharges subject to regulation under the Clean Water Act. Specifically, the EPA seeks comments on whether Clean Water Act jurisdiction should cover discharges to groundwater that reach surface water via a direct hydrologic connection. Extending Clean Water Act jurisdiction to such discharges could potentially subject certain releases from CCR impoundments to additional permitting and remediation requirements. PPL, LKE, LG&E and KU are unable to predict the future regulatory developments or potential impacts on current LG&E and KU compliance plans. ELGs In September 2015, the EPA released its final ELGs for wastewater discharge permits for new and existing steam electric generating facilities. The rule provides strict technology-based discharge limitations for control of pollutants in scrubber wastewater, fly ash and bottom ash transport water, mercury control wastewater, gasification wastewater and combustion residual leachate. The new guidelines require deployment of additional control technologies providing physical, chemical and biological treatment of wastewaters. The guidelines also mandate operational changes including "no discharge" requirements for fly ash and bottom ash transport waters and mercury control wastewaters. The implementation date for individual generating stations will be determined by the states on a case-by-case basis according to criteria provided by the EPA. Industry groups, environmental groups, individual companies and others have filed legal challenges to the final rule, which have been consolidated before the U.S. Court of Appeals for the Fifth Circuit. In April 2017, the EPA announced that it would grant petitions for reconsideration of the rule. In September 2017, the EPA published in the Federal Register a proposed rule that would postpone the compliance date for requirements relating to bottom ash transport waters and scrubber wastewaters discharge limits. The EPA expects to complete its reconsideration of best available technology standards by the fall of 2020. Upon completion of the ongoing regulatory proceedings, the rule will be implemented by the states in the course of their normal permitting activities. LG&E and KU are developing compliance strategies and schedules. PPL, LKE, LG&E and KU are unable to predict the outcome of the EPA's pending reconsideration of the rule or fully estimate compliance costs or timing. Additionally, certain aspects of these compliance plans and estimates relate to developments in state water quality standards, which are separate from the ELG rule or its implementation. Costs to comply with ELGs or other discharge limits, which are expected to be significant, are subject to rate recovery. Seepages and Groundwater Infiltration Seepages or groundwater infiltration have been detected at active and retired wastewater basins and landfills at various LG&E and KU plants. LG&E and KU have completed, or are completing, assessments of seepages or groundwater infiltration at various facilities and have completed, or are working with agencies to implement, further testing, monitoring or abatement measures, where applicable. Depending on the circumstances in each case, certain costs, which may be subject to rate recovery, could be significant. LG&E and KU cannot currently estimate a possible loss or range of possible losses related to this matter. (All Registrants) Other Issues In June 2016, the "Frank Lautenberg Chemical Safety Act" took effect as an amendment to the Toxic Substance Control Act (TSCA). The Act made no changes to the pre-existing TSCA rules as it pertains to polychlorinated biphenyls (PCB). The EPA continues to reassess its PCB regulations as part of the 2010 Advanced Notice of Proposed Rulemaking (ANPRM). The EPA's ANPRM rulemaking is to occur in two phases. Only the second part of the rule is applicable to PPL operations. This part of the rule relates to the use of PCBs in electrical equipment and natural gas pipelines, as well as continued use of PCB-contaminated porous surfaces. Although the first rulemaking will not directly affect the Registrants' operations, it may indicate certain approaches or principles to occur in the later rulemaking which may affect Registrants' facilities in the United States, including phase-out of some or all equipment containing PCBs. Should such a phase-out be required, the costs, which are subject to rate recovery, could be significant. Currently the EPA is planning a review of part two later in 2018. Superfund and Other Remediation PPL Electric is potentially responsible for a share of the costs at several sites listed by the EPA under the federal Superfund program, including the Columbia Gas Plant site and the Brodhead site. Clean-up actions have been or are being undertaken at all of these sites, the costs of which have not been, and are not expected to be, significant to PPL Electric. PPL Electric, LG&E and KU are investigating, responding to agency inquiries, implementing various preventative measures, remediating, or have completed the remediation of, several sites that were not addressed under a regulatory program such as Superfund, but for which PPL Electric, LG&E and KU may be liable for remediation. These include a number of former coal gas manufacturing plants in Pennsylvania and Kentucky previously owned or operated or currently owned by predecessors or affiliates of PPL Electric, LG&E and KU. To date, the costs of these sites have not been significant. There are additional sites, formerly owned or operated by PPL Electric, LG&E and KU predecessors or affiliates. PPL Electric, LG&E and KU lack sufficient information about such additional sites to estimate any potential liability they may have or a range of reasonably possible losses, if any, related to these matters. As of March 31, 2018 and December 31, 2017, PPL Electric had a recorded liability of $11 million and $10 million representing its best estimate of the probable loss incurred to remediate the sites noted above. Depending on the outcome of investigations at sites where investigations have not begun or been completed, or developments at sites for which information is incomplete, additional costs of remediation could be incurred; however, such costs are not expected to be significant. The EPA is evaluating the risks associated with polycyclic aromatic hydrocarbons and naphthalene, chemical by-products of coal gas manufacturing. As a result of the EPA's evaluation, individual states may establish stricter standards for water quality and soil cleanup. This could require several PPL subsidiaries to take more extensive assessment and remedial actions at former coal gas manufacturing plants. PPL, PPL Electric, LKE, LG&E and KU cannot estimate a range of reasonably possible losses, if any, related to these matters. From time to time, PPL's subsidiaries in the United States undertake testing, monitoring or remedial action in response to notices of violations, spills or other releases at various on-site and off-site locations, negotiate with the EPA and state and local agencies regarding actions necessary to comply with applicable requirements, negotiate with property owners and other third parties alleging impacts from PPL's operations and undertake similar actions necessary to resolve environmental matters that arise in the course of normal operations. Based on analyses to date, resolution of these environmental matters is not expected to have a significant adverse impact on the operations of PPL Electric, LG&E and KU. Future cleanup or remediation work at sites under review, or at sites not yet identified, may result in significant additional costs for PPL, PPL Electric, LKE, LG&E and KU. Insurance policies maintained by LKE, LG&E and KU may be available to cover certain of the costs or other obligations related to these matters but the amount of insurance coverage or reimbursement cannot be estimated or assured. Other Guarantees and Other Assurances (All Registrants) In the normal course of business, the Registrants enter into agreements that provide financial performance assurance to third parties on behalf of certain subsidiaries. Such agreements include, for example, guarantees, stand-by letters of credit issued by financial institutions and surety bonds issued by insurance companies. These agreements are entered into primarily to support or enhance the creditworthiness attributed to a subsidiary on a stand-alone basis or to facilitate the commercial activities in which these subsidiaries engage. (PPL) PPL fully and unconditionally guarantees all of the debt securities of PPL Capital Funding. (All Registrants) The table below details guarantees provided as of March 31, 2018 . "Exposure" represents the estimated maximum potential amount of future payments that could be required to be made under the guarantee. The probability of expected payment/performance under each of these guarantees is remote except for "WPD guarantee of pension and other obligations of unconsolidated entities." The total recorded liability at March 31, 2018 was $7 million for PPL and not significant for LKE. The total recorded liability at December 31, 2017 was $17 million for PPL and $11 million for LKE. For reporting purposes, on a consolidated basis, all guarantees of PPL Electric, LKE, LG&E and KU also apply to PPL, and all guarantees of LG&E and KU also apply to LKE. Exposure at Expiration PPL Indemnifications related to the WPD Midlands acquisition (a) WPD indemnifications for entities in liquidation and sales of assets $ 11 (b) 2020 WPD guarantee of pension and other obligations of unconsolidated entities 99 (c) PPL Electric Guarantee of inventory value 1

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2018
PPL Electric Utilities Corp [Member]
Related Party Transactions [Line Items]
Related Party Transactions	11. Related Party Transactions Support Costs (PPL Electric, LKE, LG&E and KU) PPL Services, PPL EU Services and LKS provide PPL, PPL Electric, LKE, their respective subsidiaries, including LG&E and KU, and each other with administrative, management and support services. For all service companies, the costs of these services are charged to the respective recipients as direct support costs. General costs that cannot be directly attributed to a specific entity are allocated and charged to the respective recipients as indirect support costs. PPL Services and PPL EU Services use a three-factor methodology that includes the applicable recipients' invested capital, operation and maintenance expenses and number of employees to allocate indirect costs. PPL Services may also use a ratio of overall direct and indirect costs or a weighted average cost ratio. LKS bases its indirect allocations on the subsidiaries' number of employees, total assets, revenues, number of customers and/or other statistical information. PPL Services, PPL EU Services and LKS charged the following amounts for the periods ended March 31 , including amounts applied to accounts that are further distributed between capital and expense on the books of the recipients, based on methods that are believed to be reasonable. Three Months 2018 2017 PPL Electric from PPL Services $ 16 $ 51 LKE from PPL Services 7 6 PPL Electric from PPL EU Services 35 18 LG&E from LKS 38 44 KU from LKS 42 44 In addition to the charges for services noted above, LKS makes payments on behalf of LG&E and KU for fuel purchases and other costs for products or services provided by third parties. LG&E and KU also provide services to each other and to LKS. Billings between LG&E and KU relate to labor and overheads associated with union and hourly employees performing work for the other company, charges related to jointly-owned generating units and other miscellaneous charges. Tax settlements between LKE and LG&E and KU are reimbursed through LKS. Intercompany Borrowings (PPL Electric) PPL Energy Funding maintains a $400 million revolving line of credit with a PPL Electric subsidiary. No balance was outstanding at March 31, 2018 and December 31, 2017. The interest rates on borrowings are equal to one-month LIBOR plus a spread. (LKE) LKE maintains a revolving line of credit with a PPL Energy Funding subsidiary whereby LKE can borrow funds on a short-term basis at market-based rates. In February 2018, the revolving line of credit was increased by $25 million and the limit as of March 31, 2018 was $300 million . The interest rates on borrowings are equal to one-month LIBOR plus a spread. At March 31, 2018 and December 31, 2017 , $237 million and $225 million were outstanding and reflected in "Notes payable with affiliates" on the Balance Sheets. The interest rates on the outstanding borrowing at March 31, 2018 and December 31, 2017 were 3.17% and 2.87% . LKE maintains a $400 million ten -year note with a PPL affiliate with an interest rate of 3.5% . At March 31, 2018 and December 31, 2017 , the note was reflected in "Long-term debt to affiliate" on the Balance Sheets. Interest expense on this note was $4 million for the three months ending March 31, 2018 and 2017. In May 2018, LKE borrowed $250 million from a PPL affiliate through the issuance of a 4% ten-year note due 2028 with interest due in May and November. The proceeds were used to repay its outstanding notes payable with a PPL Energy Funding subsidiary. Other (PPL Electric, LG&E and KU) See Note 9 for discussions regarding intercompany allocations associated with defined benefits.
LG And E And KU Energy LLC [Member]
Related Party Transactions [Line Items]
Related Party Transactions	11. Related Party Transactions Support Costs (PPL Electric, LKE, LG&E and KU) PPL Services, PPL EU Services and LKS provide PPL, PPL Electric, LKE, their respective subsidiaries, including LG&E and KU, and each other with administrative, management and support services. For all service companies, the costs of these services are charged to the respective recipients as direct support costs. General costs that cannot be directly attributed to a specific entity are allocated and charged to the respective recipients as indirect support costs. PPL Services and PPL EU Services use a three-factor methodology that includes the applicable recipients' invested capital, operation and maintenance expenses and number of employees to allocate indirect costs. PPL Services may also use a ratio of overall direct and indirect costs or a weighted average cost ratio. LKS bases its indirect allocations on the subsidiaries' number of employees, total assets, revenues, number of customers and/or other statistical information. PPL Services, PPL EU Services and LKS charged the following amounts for the periods ended March 31 , including amounts applied to accounts that are further distributed between capital and expense on the books of the recipients, based on methods that are believed to be reasonable. Three Months 2018 2017 PPL Electric from PPL Services $ 16 $ 51 LKE from PPL Services 7 6 PPL Electric from PPL EU Services 35 18 LG&E from LKS 38 44 KU from LKS 42 44 In addition to the charges for services noted above, LKS makes payments on behalf of LG&E and KU for fuel purchases and other costs for products or services provided by third parties. LG&E and KU also provide services to each other and to LKS. Billings between LG&E and KU relate to labor and overheads associated with union and hourly employees performing work for the other company, charges related to jointly-owned generating units and other miscellaneous charges. Tax settlements between LKE and LG&E and KU are reimbursed through LKS. Intercompany Borrowings (PPL Electric) PPL Energy Funding maintains a $400 million revolving line of credit with a PPL Electric subsidiary. No balance was outstanding at March 31, 2018 and December 31, 2017. The interest rates on borrowings are equal to one-month LIBOR plus a spread. (LKE) LKE maintains a revolving line of credit with a PPL Energy Funding subsidiary whereby LKE can borrow funds on a short-term basis at market-based rates. In February 2018, the revolving line of credit was increased by $25 million and the limit as of March 31, 2018 was $300 million . The interest rates on borrowings are equal to one-month LIBOR plus a spread. At March 31, 2018 and December 31, 2017 , $237 million and $225 million were outstanding and reflected in "Notes payable with affiliates" on the Balance Sheets. The interest rates on the outstanding borrowing at March 31, 2018 and December 31, 2017 were 3.17% and 2.87% . LKE maintains a $400 million ten -year note with a PPL affiliate with an interest rate of 3.5% . At March 31, 2018 and December 31, 2017 , the note was reflected in "Long-term debt to affiliate" on the Balance Sheets. Interest expense on this note was $4 million for the three months ending March 31, 2018 and 2017. In May 2018, LKE borrowed $250 million from a PPL affiliate through the issuance of a 4% ten-year note due 2028 with interest due in May and November. The proceeds were used to repay its outstanding notes payable with a PPL Energy Funding subsidiary. Other (PPL Electric, LG&E and KU) See Note 9 for discussions regarding intercompany allocations associated with defined benefits.
Louisville Gas And Electric Co [Member]
Related Party Transactions [Line Items]
Related Party Transactions	11. Related Party Transactions Support Costs (PPL Electric, LKE, LG&E and KU) PPL Services, PPL EU Services and LKS provide PPL, PPL Electric, LKE, their respective subsidiaries, including LG&E and KU, and each other with administrative, management and support services. For all service companies, the costs of these services are charged to the respective recipients as direct support costs. General costs that cannot be directly attributed to a specific entity are allocated and charged to the respective recipients as indirect support costs. PPL Services and PPL EU Services use a three-factor methodology that includes the applicable recipients' invested capital, operation and maintenance expenses and number of employees to allocate indirect costs. PPL Services may also use a ratio of overall direct and indirect costs or a weighted average cost ratio. LKS bases its indirect allocations on the subsidiaries' number of employees, total assets, revenues, number of customers and/or other statistical information. PPL Services, PPL EU Services and LKS charged the following amounts for the periods ended March 31 , including amounts applied to accounts that are further distributed between capital and expense on the books of the recipients, based on methods that are believed to be reasonable. Three Months 2018 2017 PPL Electric from PPL Services $ 16 $ 51 LKE from PPL Services 7 6 PPL Electric from PPL EU Services 35 18 LG&E from LKS 38 44 KU from LKS 42 44 In addition to the charges for services noted above, LKS makes payments on behalf of LG&E and KU for fuel purchases and other costs for products or services provided by third parties. LG&E and KU also provide services to each other and to LKS. Billings between LG&E and KU relate to labor and overheads associated with union and hourly employees performing work for the other company, charges related to jointly-owned generating units and other miscellaneous charges. Tax settlements between LKE and LG&E and KU are reimbursed through LKS. Intercompany Borrowings (PPL Electric) PPL Energy Funding maintains a $400 million revolving line of credit with a PPL Electric subsidiary. No balance was outstanding at March 31, 2018 and December 31, 2017. The interest rates on borrowings are equal to one-month LIBOR plus a spread. (LKE) LKE maintains a revolving line of credit with a PPL Energy Funding subsidiary whereby LKE can borrow funds on a short-term basis at market-based rates. In February 2018, the revolving line of credit was increased by $25 million and the limit as of March 31, 2018 was $300 million . The interest rates on borrowings are equal to one-month LIBOR plus a spread. At March 31, 2018 and December 31, 2017 , $237 million and $225 million were outstanding and reflected in "Notes payable with affiliates" on the Balance Sheets. The interest rates on the outstanding borrowing at March 31, 2018 and December 31, 2017 were 3.17% and 2.87% . LKE maintains a $400 million ten -year note with a PPL affiliate with an interest rate of 3.5% . At March 31, 2018 and December 31, 2017 , the note was reflected in "Long-term debt to affiliate" on the Balance Sheets. Interest expense on this note was $4 million for the three months ending March 31, 2018 and 2017. In May 2018, LKE borrowed $250 million from a PPL affiliate through the issuance of a 4% ten-year note due 2028 with interest due in May and November. The proceeds were used to repay its outstanding notes payable with a PPL Energy Funding subsidiary. Other (PPL Electric, LG&E and KU) See Note 9 for discussions regarding intercompany allocations associated with defined benefits.
Kentucky Utilities Co [Member]
Related Party Transactions [Line Items]
Related Party Transactions	11. Related Party Transactions Support Costs (PPL Electric, LKE, LG&E and KU) PPL Services, PPL EU Services and LKS provide PPL, PPL Electric, LKE, their respective subsidiaries, including LG&E and KU, and each other with administrative, management and support services. For all service companies, the costs of these services are charged to the respective recipients as direct support costs. General costs that cannot be directly attributed to a specific entity are allocated and charged to the respective recipients as indirect support costs. PPL Services and PPL EU Services use a three-factor methodology that includes the applicable recipients' invested capital, operation and maintenance expenses and number of employees to allocate indirect costs. PPL Services may also use a ratio of overall direct and indirect costs or a weighted average cost ratio. LKS bases its indirect allocations on the subsidiaries' number of employees, total assets, revenues, number of customers and/or other statistical information. PPL Services, PPL EU Services and LKS charged the following amounts for the periods ended March 31 , including amounts applied to accounts that are further distributed between capital and expense on the books of the recipients, based on methods that are believed to be reasonable. Three Months 2018 2017 PPL Electric from PPL Services $ 16 $ 51 LKE from PPL Services 7 6 PPL Electric from PPL EU Services 35 18 LG&E from LKS 38 44 KU from LKS 42 44 In addition to the charges for services noted above, LKS makes payments on behalf of LG&E and KU for fuel purchases and other costs for products or services provided by third parties. LG&E and KU also provide services to each other and to LKS. Billings between LG&E and KU relate to labor and overheads associated with union and hourly employees performing work for the other company, charges related to jointly-owned generating units and other miscellaneous charges. Tax settlements between LKE and LG&E and KU are reimbursed through LKS. Intercompany Borrowings (PPL Electric) PPL Energy Funding maintains a $400 million revolving line of credit with a PPL Electric subsidiary. No balance was outstanding at March 31, 2018 and December 31, 2017. The interest rates on borrowings are equal to one-month LIBOR plus a spread. (LKE) LKE maintains a revolving line of credit with a PPL Energy Funding subsidiary whereby LKE can borrow funds on a short-term basis at market-based rates. In February 2018, the revolving line of credit was increased by $25 million and the limit as of March 31, 2018 was $300 million . The interest rates on borrowings are equal to one-month LIBOR plus a spread. At March 31, 2018 and December 31, 2017 , $237 million and $225 million were outstanding and reflected in "Notes payable with affiliates" on the Balance Sheets. The interest rates on the outstanding borrowing at March 31, 2018 and December 31, 2017 were 3.17% and 2.87% . LKE maintains a $400 million ten -year note with a PPL affiliate with an interest rate of 3.5% . At March 31, 2018 and December 31, 2017 , the note was reflected in "Long-term debt to affiliate" on the Balance Sheets. Interest expense on this note was $4 million for the three months ending March 31, 2018 and 2017. In May 2018, LKE borrowed $250 million from a PPL affiliate through the issuance of a 4% ten-year note due 2028 with interest due in May and November. The proceeds were used to repay its outstanding notes payable with a PPL Energy Funding subsidiary. Other (PPL Electric, LG&E and KU) See Note 9 for discussions regarding intercompany allocations associated with defined benefits.

Other Income (Expense) - net

Other Income (Expense) - net	3 Months Ended
	Mar. 31, 2018
Other Income (Expense) Net [Line Items]
Other Income (Expense) - net	12. Other Income (Expense) - net (PPL) The details of "Other Income (Expense) - net" for the three months ended March 31 , were: PPL 2018 2017 Other Income Defined benefit plans - non-service credits (Note 9) $ 68 $ 38 AFUDC - equity component 5 2 Miscellaneous 1 9 Total Other Income 74 49 Other Expense Economic foreign currency exchange contracts (Note 14) 112 43 Charitable contributions 4 4 Miscellaneous 1 11 Total Other Expense 117 58 Other Income (Expense) - net $ (43 ) $ (9 ) (PPL Electric) The details of "Other Income (Expense) - net" for the three months ended March 31 , were: PPL Electric 2018 2017 Other Income AFUDC - equity component $ 5 $ 2 Defined benefit plans - non-service credits (Note 9) 2 — Total Other Income 7 2 Other Expense Charitable contributions 1 1 Defined benefit plans - non-service costs (Note 9) — 1 Total Other Expense 1 2 Other Income (Expense) - net $ 6 $ —
PPL Electric Utilities Corp [Member]
Other Income (Expense) Net [Line Items]
Other Income (Expense) - net	12. Other Income (Expense) - net (PPL) The details of "Other Income (Expense) - net" for the three months ended March 31 , were: PPL 2018 2017 Other Income Defined benefit plans - non-service credits (Note 9) $ 68 $ 38 AFUDC - equity component 5 2 Miscellaneous 1 9 Total Other Income 74 49 Other Expense Economic foreign currency exchange contracts (Note 14) 112 43 Charitable contributions 4 4 Miscellaneous 1 11 Total Other Expense 117 58 Other Income (Expense) - net $ (43 ) $ (9 ) (PPL Electric) The details of "Other Income (Expense) - net" for the three months ended March 31 , were: PPL Electric 2018 2017 Other Income AFUDC - equity component $ 5 $ 2 Defined benefit plans - non-service credits (Note 9) 2 — Total Other Income 7 2 Other Expense Charitable contributions 1 1 Defined benefit plans - non-service costs (Note 9) — 1 Total Other Expense 1 2 Other Income (Expense) - net $ 6 $ —

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	13. Fair Value Measurements (All Registrants) Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (an exit price). A market approach (generally, data from market transactions), an income approach (generally, present value techniques and option-pricing models) and/or a cost approach (generally, replacement cost) are used to measure the fair value of an asset or liability, as appropriate. These valuation approaches incorporate inputs such as observable, independent market data and/or unobservable data that management believes are predicated on the assumptions market participants would use to price an asset or liability. These inputs may incorporate, as applicable, certain risks such as nonperformance risk, which includes credit risk. The fair value of a group of financial assets and liabilities is measured on a net basis. Transfers between levels are recognized at end-of-reporting-period values. During the three months ended March 31, 2018 and 2017 , there were no transfers between Level 1 and Level 2. See Note 1 in each Registrant's 2017 Form 10-K for information on the levels in the fair value hierarchy. Recurring Fair Value Measurements The assets and liabilities measured at fair value were: March 31, 2018 December 31, 2017 Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 PPL Assets Cash and cash equivalents $ 629 $ 629 $ — $ — $ 485 $ 485 $ — $ — Restricted cash and cash equivalents (a) 24 24 — — 26 26 — — Price risk management assets (b): Foreign currency contracts 97 — 97 — 163 — 163 — Cross-currency swaps 79 — 79 — 101 — 101 — Total price risk management assets 176 — 176 — 264 — 264 — Total assets $ 829 $ 653 $ 176 $ — $ 775 $ 511 $ 264 $ — Liabilities Price risk management liabilities (b): Interest rate swaps $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — Foreign currency contracts 167 — 167 — 148 — 148 — Total price risk management liabilities $ 189 $ — $ 189 $ — $ 174 $ — $ 174 $ — PPL Electric Assets Cash and cash equivalents $ 20 $ 20 $ — $ — $ 49 $ 49 $ — $ — Restricted cash and cash equivalents (a) 2 2 — — 2 2 — — Total assets $ 22 $ 22 $ — $ — $ 51 $ 51 $ — $ — LKE Assets Cash and cash equivalents $ 27 $ 27 $ — $ — $ 30 $ 30 $ — $ — Total assets $ 27 $ 27 $ — $ — $ 30 $ 30 $ — $ — Liabilities Price risk management liabilities: Interest rate swaps $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — Total price risk management liabilities $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — LG&E Assets Cash and cash equivalents $ 14 $ 14 $ — $ — $ 15 $ 15 $ — $ — Total assets $ 14 $ 14 $ — $ — $ 15 $ 15 $ — $ — Liabilities Price risk management liabilities: Interest rate swaps $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — Total price risk management liabilities $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — March 31, 2018 December 31, 2017 Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 KU Assets Cash and cash equivalents $ 11 $ 11 $ — $ — $ 15 $ 15 $ — $ — Total assets $ 11 $ 11 $ — $ — $ 15 $ 15 $ — $ — (a) Current portion is included in "Other current assets" and long-term portion is included in "Other noncurrent assets" on the Balance Sheets. (b) Current portion is included in "Price risk management assets" and "Other current liabilities" and noncurrent portion is included in "Price risk management assets" and "Other deferred credits and noncurrent liabilities" on the Balance Sheets. Price Risk Management Assets/Liabilities - Interest Rate Swaps/Foreign Currency Contracts/Cross-Currency Swaps ( PPL, LKE, LG&E and KU) To manage interest rate risk, PPL, LKE, LG&E and KU use interest rate contracts such as forward-starting swaps, floating-to-fixed swaps and fixed-to-floating swaps. To manage foreign currency risk, PPL uses foreign currency contracts such as forwards, options and cross-currency swaps that contain characteristics of both interest rate and foreign currency contracts. An income approach is used to measure the fair value of these contracts, utilizing readily observable inputs, such as forward interest rates (e.g., LIBOR and government security rates) and forward foreign currency exchange rates (e.g., GBP), as well as inputs that may not be observable, such as credit valuation adjustments. In certain cases, market information cannot practicably be obtained to value credit risk and therefore internal models are relied upon. These models use projected probabilities of default and estimated recovery rates based on historical observances. When the credit valuation adjustment is significant to the overall valuation, the contracts are classified as Level 3. Financial Instruments Not Recorded at Fair Value (All Registrants) The carrying amounts of long-term debt on the Balance Sheets and their estimated fair values are set forth below. Long-term debt is classified as Level 2. The effect of third-party credit enhancements is not included in the fair value measurement. March 31, 2018 December 31, 2017 Carrying Fair Value Carrying Fair Value PPL $ 20,464 $ 23,577 $ 20,195 $ 23,783 PPL Electric 3,298 3,632 3,298 3,769 LKE 5,259 5,654 5,159 5,670 LG&E 1,808 1,925 1,709 1,865 KU 2,329 2,546 2,328 2,605 (a) Amounts are net of debt issuance costs. The carrying amounts of other current financial instruments (except for long-term debt due within one year) approximate their fair values because of their short-term nature.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	14. Derivative Instruments and Hedging Activities Risk Management Objectives (All Registrants) PPL has a risk management policy approved by the Board of Directors to manage market risk associated with commodities, interest rates on debt issuances and foreign exchange (including price, liquidity and volumetric risk) and credit risk (including non-performance risk and payment default risk). The Risk Management Committee, comprised of senior management and chaired by the Senior Director-Risk Management, oversees the risk management function. Key risk control activities designed to ensure compliance with the risk policy and detailed programs include, but are not limited to, credit review and approval, validation of transactions, verification of risk and transaction limits, value-at-risk analyses (VaR, a statistical model that attempts to estimate the value of potential loss over a given holding period under normal market conditions at a given confidence level) and the coordination and reporting of the Enterprise Risk Management program. Market Risk Market risk includes the potential loss that may be incurred as a result of price changes associated with a particular financial or commodity instrument as well as market liquidity and volumetric risks. Forward contracts, futures contracts, options, swaps and structured transactions are utilized as part of risk management strategies to minimize unanticipated fluctuations in earnings caused by changes in commodity prices, interest rates and foreign currency exchange rates. Many of these contracts meet the definition of a derivative. All derivatives are recognized on the Balance Sheets at their fair value, unless NPNS is elected. The following summarizes the market risks that affect PPL and its subsidiaries. Interest Rate Risk • PPL and its subsidiaries are exposed to interest rate risk associated with forecasted fixed-rate and existing floating-rate debt issuances. PPL and WPD hold over-the-counter cross currency swaps to limit exposure to market fluctuations on interest and principal payments from changes in foreign currency exchange rates and interest rates. PPL, LKE and LG&E utilize over-the-counter interest rate swaps to limit exposure to market fluctuations on floating-rate debt. PPL, LKE, LG&E and KU utilize forward starting interest rate swaps to hedge changes in benchmark interest rates, when appropriate, in connection with future debt issuances. • PPL and its subsidiaries are exposed to interest rate risk associated with debt securities and derivatives held by defined benefit plans. This risk is significantly mitigated to the extent that the plans are sponsored at, or sponsored on behalf of, the regulated domestic utilities and for certain plans at WPD due to the recovery methods in place. Foreign Currency Risk (PPL) • PPL is exposed to foreign currency exchange risk primarily associated with its investments in and earnings of U.K. affiliates. (All Registrants) Commodity Price Risk PPL is exposed to commodity price risk through its domestic subsidiaries as described below. • PPL Electric is required to purchase electricity to fulfill its obligation as a PLR. Potential commodity price risk is mitigated through its PUC-approved cost recovery mechanism and full-requirement supply agreements to serve its PLR customers which transfer the risk to energy suppliers. • LG&E's and KU's rates include certain mechanisms for fuel, fuel-related expenses and energy purchases. In addition, LG&E's rates include a mechanism for natural gas supply expenses. These mechanisms generally provide for timely recovery of market price fluctuations associated with these expenses. Volumetric Risk PPL is exposed to volumetric risk through its subsidiaries as described below. • WPD is exposed to volumetric risk which is significantly mitigated as a result of the method of regulation in the U.K. Under the RIIO-ED1 price control regulations, recovery of such exposure occurs on a two year lag. See Note 1 in PPL's 2017 Form 10-K for additional information on revenue recognition under RIIO-ED1. • PPL Electric, LG&E and KU are exposed to volumetric risk on retail sales, mainly due to weather and other economic conditions for which there is limited mitigation between rate cases. Equity Securities Price Risk • PPL and its subsidiaries are exposed to equity securities price risk associated with the fair value of the defined benefit plans' assets. This risk is significantly mitigated at the regulated domestic utilities and for certain plans at WPD due to the recovery methods in place. • PPL is exposed to equity securities price risk from future stock sales and/or purchases. Credit Risk Credit risk is the potential loss that may be incurred due to a counterparty's non-performance. PPL is exposed to credit risk from "in-the-money" interest rate and foreign currency derivatives with financial institutions, as well as additional credit risk through certain of its subsidiaries, as discussed below. In the event a supplier of PPL Electric, LG&E or KU defaults on its obligation, those Registrants would be required to seek replacement power or replacement fuel in the market. In general, subject to regulatory review or other processes, appropriate incremental costs incurred by these entities would be recoverable from customers through applicable rate mechanisms, thereby mitigating the financial risk for these entities. PPL and its subsidiaries have credit policies in place to manage credit risk, including the use of an established credit approval process, daily monitoring of counterparty positions and the use of master netting agreements or provisions. These agreements generally include credit mitigation provisions, such as margin, prepayment or collateral requirements. PPL and its subsidiaries may request additional credit assurance, in certain circumstances, in the event that the counterparties' credit ratings fall below investment grade, their tangible net worth falls below specified percentages or their exposures exceed an established credit limit. Master Netting Arrangements (PPL, LKE, LG&E and KU) Net derivative positions on the balance sheets are not offset against the right to reclaim cash collateral (a receivable) or the obligation to return cash collateral (a payable) under master netting arrangements. PPL had a $16 million obligation to return cash collateral under master netting arrangements at March 31, 2018 and a $20 million obligation to return cash collateral under master netting arrangements at December 31, 2017 . PPL had a $5 million obligation to post cash collateral under master netting arrangements at March 31, 2018 and no cash collateral posted under master netting arrangements at December 31, 2017. LKE, LG&E and KU had no obligation to return cash collateral under master netting arrangements at March 31, 2018 and December 31, 2017 . LKE, LG&E and KU had no cash collateral posted under master netting arrangements at March 31, 2018 and December 31, 2017 . See "Offsetting Derivative Instruments" below for a summary of derivative positions presented in the balance sheets where a right of setoff exists under these arrangements. Interest Rate Risk (All Registrants) PPL and its subsidiaries issue debt to finance their operations, which exposes them to interest rate risk. A variety of financial derivative instruments are utilized to adjust the mix of fixed and floating interest rates in their debt portfolios, adjust the duration of the debt portfolios and lock in benchmark interest rates in anticipation of future financing, when appropriate. Risk limits under PPL's risk management program are designed to balance risk exposure to volatility in interest expense and changes in the fair value of the debt portfolio due to changes in benchmark interest rates. In addition, the interest rate risk of certain subsidiaries is potentially mitigated as a result of the existing regulatory framework or the timing of rate cases. Cash Flow Hedges (PPL) Interest rate risks include exposure to adverse interest rate movements for outstanding variable rate debt and for future anticipated financings. Financial interest rate swap contracts that qualify as cash flow hedges may be entered into to hedge floating interest rate risk associated with both existing and anticipated debt issuances. PPL held no such contracts at March 31, 2018. For the three months ended March 31, 2018 and 2017, PPL had no hedge ineffectiveness associated with interest rate derivatives. At March 31, 2018 , PPL held an aggregate notional value in cross-currency interest rate swap contracts of $702 million that range in maturity from 2021 through 2028 to hedge the interest payments and principal of WPD's U.S. dollar-denominated senior notes. For the three months ended March 31, 2018 and 2017 , PPL had no hedge ineffectiveness associated with cross-currency interest rate swap derivatives. Cash flow hedges are discontinued if it is no longer probable that the original forecasted transaction will occur by the end of the originally specified time period and any amounts previously recorded in AOCI are reclassified into earnings once it is determined that the hedged transaction is not probable of occurring. For the three months ended March 31, 2018, PPL had no cash flow hedges reclassified into earnings associated with discontinued cash flow hedges. For the three months ended March 31, 2017, PPL had an insignificant amount of cash flow hedges reclassified into earnings associated with discontinued cash flow hedges. At March 31, 2018 , the amount of accumulated net unrecognized after-tax gains (losses) on qualifying derivatives expected to be reclassified into earnings during the next 12 months is insignificant . Amounts are reclassified as the hedged interest expense is recorded. Economic Activity (PPL, LKE and LG&E) LG&E enters into interest rate swap contracts that economically hedge interest payments on variable rate debt. Because realized gains and losses from the swaps, including terminated swap contracts, are recoverable through regulated rates, any subsequent changes in fair value of these derivatives are included in regulatory assets or liabilities until they are realized as interest expense. Realized gains and losses are recognized in "Interest Expense" on the Statements of Income at the time the underlying hedged interest expense is recorded. At March 31, 2018 , LG&E held contracts with a notional amount of $147 million that range in maturity through 2033 . Foreign Currency Risk (PPL) PPL is exposed to foreign currency risk, primarily through investments in and earnings of U.K. affiliates. PPL has adopted a foreign currency risk management program designed to hedge certain foreign currency exposures, including firm commitments, recognized assets or liabilities, anticipated transactions and net investments. In addition, PPL enters into financial instruments to protect against foreign currency translation risk of expected GBP earnings. Net Investment Hedges PPL enters into foreign currency contracts on behalf of a subsidiary to protect the value of a portion of its net investment in WPD. The contracts outstanding at March 31, 2018 had a notional amount of £140 million (approximately $195 million based on contracted rates). The settlement dates of these contracts are in June 2018 . At March 31, 2018 and December 31, 2017 , PPL had $20 million and $22 million of accumulated net investment hedge after tax gains (losses) that were included in the foreign currency translation adjustment component of AOCI. Economic Activity PPL enters into foreign currency contracts on behalf of a subsidiary to economically hedge GBP-denominated anticipated earnings. At March 31, 2018 , the total exposure hedged by PPL was approximately £2.1 billion (approximately $2.9 billion based on contracted rates). These contracts have termination dates ranging from April 2018 through August 2020 . Accounting and Reporting (All Registrants) All derivative instruments are recorded at fair value on the Balance Sheet as an asset or liability unless NPNS is elected. NPNS contracts for PPL and PPL Electric include certain full-requirement purchase contracts and other physical purchase contracts. Changes in the fair value of derivatives not designated as NPNS are recognized in earnings unless specific hedge accounting criteria are met and designated as such, except for the changes in fair values of LG&E's interest rate swaps that are recognized as regulatory assets or regulatory liabilities. See Note 7 for amounts recorded in regulatory assets and regulatory liabilities at March 31, 2018 and December 31, 2017 . See Note 1 in each Registrant's 2017 Form 10-K for additional information on accounting policies related to derivative instruments. (PPL) The following table presents the fair value and location of derivative instruments recorded on the Balance Sheets. March 31, 2018 December 31, 2017 Derivatives designated as hedging instruments Derivatives not designated as hedging instruments Derivatives designated as hedging instruments Derivatives not designated as hedging instruments Assets Liabilities Assets Liabilities Assets Liabilities Assets Liabilities Current: Price Risk Management Assets/Liabilities (a): Interest rate swaps (b) $ — $ — $ — $ 4 $ — $ — $ — $ 4 Cross-currency swaps (b) 4 — — — 4 — — — Foreign currency contracts 1 2 51 75 — — 45 67 Total current 5 2 51 79 4 — 45 71 Noncurrent: Price Risk Management Assets/Liabilities (a): Interest rate swaps (b) — — — 18 — — — 22 Cross-currency swaps (b) 75 — — — 97 — — — Foreign currency contracts — — 45 90 — — 118 81 Total noncurrent 75 — 45 108 97 — 118 103 Total derivatives $ 80 $ 2 $ 96 $ 187 $ 101 $ — $ 163 $ 174 (a) Current portion is included in "Price risk management assets" and "Other current liabilities" and noncurrent portion is included in "Price risk management assets" and "Other deferred credits and noncurrent liabilities" on the Balance Sheets. (b) Excludes accrued interest, if applicable. The following tables present the pre-tax effect of derivative instruments recognized in income, OCI or regulatory assets and regulatory liabilities for the periods ended March 31, 2018 . Three Months Derivative Derivative Gain (Loss) Recognized in OCI (Effective Portion) Location of Gain (Loss) Gain (Loss) Three Months Cash Flow Hedges: Interest rate swaps $ — Interest expense $ (2 ) $ — Cross-currency swaps (24 ) Other income (expense) - net (12 ) — Total $ (24 ) $ (14 ) $ — Net Investment Hedges: Foreign currency contracts $ (1 ) Derivatives Not Designated as Location of Gain (Loss) Recognized in Hedging Instruments Income on Derivative Three Months Foreign currency contracts Other income (expense) - net $ (112 ) Interest rate swaps Interest expense (1 ) Total $ (113 ) Derivatives Not Designated as Location of Gain (Loss) Recognized as Hedging Instruments Regulatory Liabilities/Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 4 The following tables present the pre-tax effect of derivative instruments recognized in income, OCI or regulatory assets and regulatory liabilities for the periods ended March 31, 2017 . Three Months Derivative Derivative Gain (Loss) Recognized in OCI (Effective Portion) Location of Gain (Loss) Gain (Loss) Three Months Cash Flow Hedges: Interest rate swaps $ — Interest expense $ (2 ) $ (1 ) Cross-currency swaps (8 ) Interest expense 1 — Other income (expense) - net 3 — Total $ (8 ) $ 2 $ (1 ) Net Investment Hedges: Foreign currency contracts $ — Derivatives Not Designated as Location of Gain (Loss) Recognized in Hedging Instruments Income on Derivative Three Months Foreign currency contracts Other income (expense) - net $ (43 ) Interest rate swaps Interest expense (2 ) Total $ (45 ) Derivatives Not Designated as Location of Gain (Loss) Recognized as Hedging Instruments Regulatory Liabilities/Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 2 (LKE and LG&E) The following table presents the fair value and the location on the Balance Sheets of derivatives not designated as hedging instruments. March 31, 2018 December 31, 2017 Assets Liabilities Assets Liabilities Current: Price Risk Management Assets/Liabilities: Interest rate swaps $ — $ 4 $ — $ 4 Total current — 4 — 4 Noncurrent: Price Risk Management Assets/Liabilities: Interest rate swaps — 18 — 22 Total noncurrent — 18 — 22 Total derivatives $ — $ 22 $ — $ 26 The following tables present the pre-tax effect of derivatives not designated as cash flow hedges that are recognized in income or regulatory assets for the periods ended March 31, 2018 . Location of Gain (Loss) Recognized in Derivative Instruments Income on Derivatives Three Months Interest rate swaps Interest expense $ (1 ) Location of Gain (Loss) Recognized in Derivative Instruments Regulatory Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 4 The following tables present the pre-tax effect of derivatives not designated as cash flow hedges that are recognized in income or regulatory assets for the periods ended March 31, 2017 . Location of Gain (Loss) Recognized in Derivative Instruments Income on Derivatives Three Months Interest rate swaps Interest expense $ (2 ) Location of Gain (Loss) Recognized in Derivative Instruments Regulatory Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 2 (PPL, LKE, LG&E and KU) Offsetting Derivative Instruments PPL, LKE, LG&E and KU or certain of their subsidiaries have master netting arrangements in place and also enter into agreements pursuant to which they purchase or sell certain energy and other products. Under the agreements, upon termination of the agreement as a result of a default or other termination event, the non-defaulting party typically would have a right to set off amounts owed under the agreement against any other obligations arising between the two parties (whether under the agreement or not), whether matured or contingent and irrespective of the currency, place of payment or place of booking of the obligation. PPL, LKE, LG&E and KU have elected not to offset derivative assets and liabilities and not to offset net derivative positions against the right to reclaim cash collateral pledged (an asset) or the obligation to return cash collateral received (a liability) under derivatives agreements. The table below summarizes the derivative positions presented in the balance sheets where a right of setoff exists under these arrangements and related cash collateral received or pledged. Assets Liabilities Eligible for Offset Eligible for Offset Gross Derivative Instruments Cash Collateral Received Net Gross Derivative Instruments Cash Collateral Pledged Net March 31, 2018 Treasury Derivatives PPL $ 176 $ 78 $ 16 $ 82 $ 189 $ 78 $ 5 $ 106 LKE — — — — 22 — — 22 LG&E — — — — 22 — — 22 December 31, 2017 Treasury Derivatives PPL $ 264 $ 107 $ 20 $ 137 $ 174 $ 107 $ — $ 67 LKE — — — — 26 — — 26 LG&E — — — — 26 — — 26 Credit Risk-Related Contingent Features Certain derivative contracts contain credit risk-related contingent features which, when in a net liability position, would permit the counterparties to require the transfer of additional collateral upon a decrease in the credit ratings of PPL, LKE, LG&E and KU or certain of their subsidiaries. Most of these features would require the transfer of additional collateral or permit the counterparty to terminate the contract if the applicable credit rating were to fall below investment grade. Some of these features also would allow the counterparty to require additional collateral upon each downgrade in credit rating at levels that remain above investment grade. In either case, if the applicable credit rating were to fall below investment grade, and assuming no assignment to an investment grade affiliate were allowed, most of these credit contingent features require either immediate payment of the net liability as a termination payment or immediate and ongoing full collateralization on derivative instruments in net liability positions. Additionally, certain derivative contracts contain credit risk-related contingent features that require adequate assurance of performance be provided if the other party has reasonable concerns regarding the performance of PPL's, LKE's, LG&E's and KU's obligations under the contracts. A counterparty demanding adequate assurance could require a transfer of additional collateral or other security, including letters of credit, cash and guarantees from a creditworthy entity. This would typically involve negotiations among the parties. However, amounts disclosed below represent assumed immediate payment or immediate and ongoing full collateralization for derivative instruments in net liability positions with "adequate assurance" features. (PPL, LKE and LG&E) At March 31, 2018 , derivative contracts in a net liability position that contain credit risk-related contingent features, collateral posted on those positions and the related effect of a decrease in credit ratings below investment grade are summarized as follows: PPL LKE LG&E Aggregate fair value of derivative instruments in a net liability position with credit risk-related contingent features $ 101 $ 8 $ 8 Aggregate fair value of collateral posted on these derivative instruments 10 — — Aggregate fair value of additional collateral requirements in the event of a credit downgrade below investment grade (a) 91 8 8 (a) Includes the effect of net receivables and payables already recorded on the Balance Sheet.

Goodwill

Goodwill	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	15. Goodwill and Other Intangible Assets (PPL) The change in the carrying amount of goodwill for the three months ended March 31, 2018 was due to the effect of foreign currency exchange rates on the U.K. Regulated segment.

Asset Retirement Obligations

Asset Retirement Obligations	3 Months Ended
	Mar. 31, 2018
Asset Retirement Obligations [Line Items]
Asset Retirement Obligations	16. Asset Retirement Obligations (PPL, LKE, LG&E and KU) PPL's, LKE's, LG&E's and KU's ARO liabilities are primarily related to CCR closure costs. See Note 10 for information on the final CCR rule. For LKE, LG&E and KU, all ARO accretion and depreciation expenses are reclassified as a regulatory asset. ARO regulatory assets associated with certain CCR projects are amortized to expense in accordance with regulatory approvals. For other AROs, at the time of retirement, the related ARO regulatory asset is offset against the associated cost of removal regulatory liability, PP&E and ARO liability. The changes in the carrying amounts of AROs were as follows. PPL LKE LG&E KU Balance at December 31, 2017 $ 397 $ 356 $ 121 $ 235 Accretion 3 3 — 3 Effect of foreign exchange rates 1 — — — Changes in estimated timing or cost (a) (10 ) (10 ) (5 ) (5 ) Obligations settled (9 ) (9 ) (5 ) (4 ) Balance at March 31, 2018 $ 382 $ 340 $ 111 $ 229 (a) LG&E and KU recorded decreases to the existing AROs during the three months ended March 31, 2018 primarily related to the closure of CCR impoundments and associated groundwater monitoring. These revisions are the result of changes in closure plans related to expected costs and timing of closures. Further changes to AROs, capital plans or operating costs may be required as estimates of future cash flows are refined based on closure developments and regulatory or legal proceedings.
LG And E And KU Energy LLC [Member]
Asset Retirement Obligations [Line Items]
Asset Retirement Obligations	16. Asset Retirement Obligations (PPL, LKE, LG&E and KU) PPL's, LKE's, LG&E's and KU's ARO liabilities are primarily related to CCR closure costs. See Note 10 for information on the final CCR rule. For LKE, LG&E and KU, all ARO accretion and depreciation expenses are reclassified as a regulatory asset. ARO regulatory assets associated with certain CCR projects are amortized to expense in accordance with regulatory approvals. For other AROs, at the time of retirement, the related ARO regulatory asset is offset against the associated cost of removal regulatory liability, PP&E and ARO liability. The changes in the carrying amounts of AROs were as follows. PPL LKE LG&E KU Balance at December 31, 2017 $ 397 $ 356 $ 121 $ 235 Accretion 3 3 — 3 Effect of foreign exchange rates 1 — — — Changes in estimated timing or cost (a) (10 ) (10 ) (5 ) (5 ) Obligations settled (9 ) (9 ) (5 ) (4 ) Balance at March 31, 2018 $ 382 $ 340 $ 111 $ 229 (a) LG&E and KU recorded decreases to the existing AROs during the three months ended March 31, 2018 primarily related to the closure of CCR impoundments and associated groundwater monitoring. These revisions are the result of changes in closure plans related to expected costs and timing of closures. Further changes to AROs, capital plans or operating costs may be required as estimates of future cash flows are refined based on closure developments and regulatory or legal proceedings.
Louisville Gas And Electric Co [Member]
Asset Retirement Obligations [Line Items]
Asset Retirement Obligations	16. Asset Retirement Obligations (PPL, LKE, LG&E and KU) PPL's, LKE's, LG&E's and KU's ARO liabilities are primarily related to CCR closure costs. See Note 10 for information on the final CCR rule. For LKE, LG&E and KU, all ARO accretion and depreciation expenses are reclassified as a regulatory asset. ARO regulatory assets associated with certain CCR projects are amortized to expense in accordance with regulatory approvals. For other AROs, at the time of retirement, the related ARO regulatory asset is offset against the associated cost of removal regulatory liability, PP&E and ARO liability. The changes in the carrying amounts of AROs were as follows. PPL LKE LG&E KU Balance at December 31, 2017 $ 397 $ 356 $ 121 $ 235 Accretion 3 3 — 3 Effect of foreign exchange rates 1 — — — Changes in estimated timing or cost (a) (10 ) (10 ) (5 ) (5 ) Obligations settled (9 ) (9 ) (5 ) (4 ) Balance at March 31, 2018 $ 382 $ 340 $ 111 $ 229 (a) LG&E and KU recorded decreases to the existing AROs during the three months ended March 31, 2018 primarily related to the closure of CCR impoundments and associated groundwater monitoring. These revisions are the result of changes in closure plans related to expected costs and timing of closures. Further changes to AROs, capital plans or operating costs may be required as estimates of future cash flows are refined based on closure developments and regulatory or legal proceedings.
Kentucky Utilities Co [Member]
Asset Retirement Obligations [Line Items]
Asset Retirement Obligations	16. Asset Retirement Obligations (PPL, LKE, LG&E and KU) PPL's, LKE's, LG&E's and KU's ARO liabilities are primarily related to CCR closure costs. See Note 10 for information on the final CCR rule. For LKE, LG&E and KU, all ARO accretion and depreciation expenses are reclassified as a regulatory asset. ARO regulatory assets associated with certain CCR projects are amortized to expense in accordance with regulatory approvals. For other AROs, at the time of retirement, the related ARO regulatory asset is offset against the associated cost of removal regulatory liability, PP&E and ARO liability. The changes in the carrying amounts of AROs were as follows. PPL LKE LG&E KU Balance at December 31, 2017 $ 397 $ 356 $ 121 $ 235 Accretion 3 3 — 3 Effect of foreign exchange rates 1 — — — Changes in estimated timing or cost (a) (10 ) (10 ) (5 ) (5 ) Obligations settled (9 ) (9 ) (5 ) (4 ) Balance at March 31, 2018 $ 382 $ 340 $ 111 $ 229 (a) LG&E and KU recorded decreases to the existing AROs during the three months ended March 31, 2018 primarily related to the closure of CCR impoundments and associated groundwater monitoring. These revisions are the result of changes in closure plans related to expected costs and timing of closures. Further changes to AROs, capital plans or operating costs may be required as estimates of future cash flows are refined based on closure developments and regulatory or legal proceedings.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	3 Months Ended
	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss)	17. Accumulated Other Comprehensive Income (Loss) (PPL) The after-tax changes in AOCI by component for the periods ended March 31 were as follows. Foreign currency translation adjustments Unrealized gains (losses) on qualifying derivatives Defined benefit plans Equity investees' AOCI Prior service costs Actuarial gain (loss) Total PPL December 31, 2017 $ (1,089 ) $ (13 ) $ — $ (7 ) $ (2,313 ) $ (3,422 ) Amounts arising during the period 116 (20 ) — — (1 ) 95 Reclassifications from AOCI — 12 — — 36 48 Net OCI during the period 116 (8 ) — — 35 143 March 31, 2018 $ (973 ) $ (21 ) $ — $ (7 ) $ (2,278 ) $ (3,279 ) December 31, 2016 $ (1,627 ) $ (7 ) $ (1 ) $ (8 ) $ (2,135 ) $ (3,778 ) Amounts arising during the period (24 ) (6 ) — — — (30 ) Reclassifications from AOCI — (1 ) — — 32 31 Net OCI during the period (24 ) (7 ) — — 32 1 March 31, 2017 $ (1,651 ) $ (14 ) $ (1 ) $ (8 ) $ (2,103 ) $ (3,777 ) The following table presents the gains (losses) and related income taxes for reclassifications from AOCI for the periods ended March 31 . The defined benefit plan components of AOCI are not reflected in their entirety in the Statement of Income during the periods; rather, they are included in the computation of net periodic defined benefit costs (credits) and subject to capitalization. See Note 9 for additional information. Three Months Affected Line Item on the Details about AOCI 2018 2017 Statements of Income Qualifying derivatives Interest rate swaps $ (2 ) $ (3 ) Interest Expense Cross-currency swaps (12 ) 3 Other Income (Expense) - net — 1 Interest Expense Total Pre-tax (14 ) 1 Income Taxes 2 — Total After-tax (12 ) 1 Defined benefit plans Net actuarial loss (45 ) (41 ) Total Pre-tax (45 ) (41 ) Income Taxes 9 9 Total After-tax (36 ) (32 ) Total reclassifications during the period $ (48 ) $ (31 )

New Accounting Guidance Pending

New Accounting Guidance Pending Adoption	3 Months Ended
	Mar. 31, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Description of New Accounting Pronouncements Not yet Adopted [Text Block]	18. New Accounting Guidance Pending Adoption (All Registrants) Accounting for Leases In February 2016, the FASB issued accounting guidance for leases. This new guidance requires lessees to recognize a right-of-use asset and a lease liability for virtually all of their leases (other than leases that meet the definition of a short-term lease). For income statement purposes, the FASB retained a dual model for lessees, requiring leases to be classified as either operating or finance. Operating leases will result in straight-line expense (similar to current operating leases) while finance leases will result in a front-loaded expense pattern (similar to current capital leases). Classification will be based on criteria that are largely similar to those applied in current lease accounting, but without explicit bright line tests. Lessor accounting under the new guidance is similar to the current model, but updated to align with certain changes to the lessee model and the new revenue recognition standard. Similar to current practice, lessors will classify leases as operating, direct financing, or sales-type. The standard is effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted. The new standard must be adopted using a modified retrospective transition, and provides for certain practical expedients. One of these practical expedients allows entities to elect to (1) not reassess whether existing contracts contain leases, (2) carryforward the existing lease classification, and (3) not reassess initial direct costs associated with existing leases. In January 2018, the FASB also issued additional guidance that provides for a practical expedient that allows entities to elect to not evaluate land easements as leases that exist or expired before the adoption date and were not previously accounted for as leases under current lease guidance. The Registrants plan to elect these practical expedients. Transition will require application of the new guidance at the beginning of the earliest comparative period presented. The Registrants are currently assessing the impact of adopting this guidance. The Registrants will adopt this guidance effective January 1, 2019. Accounting for Financial Instrument Credit Losses In June 2016, the FASB issued accounting guidance that requires the use of a current expected credit loss (CECL) model for the measurement of credit losses on financial instruments within the scope of this guidance, which includes accounts receivable. The CECL model requires an entity to measure credit losses using historical information, current information and reasonable and supportable forecasts of future events, rather than the incurred loss impairment model required under current GAAP. For public business entities, this guidance will be applied using a modified retrospective approach and is effective for fiscal years beginning after December 15, 2019, and interim periods within those years. All entities may early adopt this guidance in beginning after December 15, 2018, including interim periods within those years. The Registrants are currently assessing the impact of adopting this guidance and the period they will adopt it. Improvements to Accounting for Hedging Activities In August 2017, the FASB issued accounting guidance that reduces complexity when applying hedge accounting as well as improves transparency about an entity's risk management activities. This guidance eliminates recognizing hedge ineffectiveness for cash flow and net investment hedges and provides for the ability to perform subsequent effectiveness assessments qualitatively. The guidance also makes certain changes to allowable methodologies such as allowing entities to apply the short-cut method to partial-term fair value hedges of interest rate risk as well as expands the ability to apply the critical terms match method to cash flow hedges of groups of forecasted transactions. The guidance also updates certain recognition and presentation requirements as well as disclosure requirements. For public business entities, this guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted. This standard must be adopted using a modified retrospective approach and provides for certain transition elections that must be made prior to the first effectiveness testing date after adoption. The Registrants are currently assessing the impact of adopting this guidance and the period they will adopt it. (PPL, LKE, LG&E and KU) Simplifying the Test for Goodwill Impairment In January 2017, the FASB issued accounting guidance that simplifies the test for goodwill impairment by eliminating the second step of the quantitative test. The second step of the quantitative test requires a calculation of the implied fair value of goodwill, which is determined in the same manner as the amount of goodwill in a business combination. Under this new guidance, an entity will now compare the estimated fair value of a reporting unit with its carrying value and recognize an impairment charge for the amount the carrying amount exceeds the fair value of the reporting unit. For public business entities, this guidance will be applied prospectively and is effective for annual or any interim goodwill impairment tests for fiscal years beginning after December 15, 2019. All entities may early adopt this guidance for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Registrants are currently assessing the impact of adopting this guidance and the period they will adopt it. (PPL and LKE) Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income In February 2018, the FASB issued accounting guidance that gives entities the option to reclassify tax effects stranded within AOCI as a result of the TCJA to retained earnings. The reclassification applies only to those stranded tax effects arising from the TCJA enactment. Certain disclosures related to the stranded tax effects, including a description of the accounting policy for releasing income tax effects from AOCI, are required. For all entities, this guidance is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Early adoption is permitted, including adoption in any interim period. The amendments should be applied either in the period of adoption or retrospectively to each period in which the effect of the change in the U.S. federal corporate income tax rate in the TCJA is recognized. The adoption of this guidance will result in PPL and LKE reclassifying $50 million and $18 million of deferred tax effects (primarily related to pension and other post-retirement benefits) stranded in AOCI as a result of the TCJA to retained earnings. The Registrants are assessing the period in which they will adopt this guidance.

Fair Value Measurements (Polici

Fair Value Measurements (Policies)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Transfer, Policy	Transfers between levels are recognized at end-of-reporting-period values.

Derivative Instruments and He29

Derivative Instruments and Hedging Activities (Policies)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives, Offsetting Fair Value Amounts, Policy	Net derivative positions on the balance sheets are not offset against the right to reclaim cash collateral (a receivable) or the obligation to return cash collateral (a payable) under master netting arrangements.

Summary of Significant Accoun30

Summary of Significant Accounting Policies Adoption of Accounting Guidance [Tables]	3 Months Ended
	Mar. 31, 2018
Adoption of Accounting Guidance [Abstract]
Schedule of Non-Service Benefits Costs (Credits) [Table Text Block]	The following provides the non-service cost components of net periodic benefits (costs) or credits presented in "Other Income (Expense) - net" in 2018 and reclassified from "Other operation and maintenance" to "Other Income (Expense) - net" in 2017 on the Statements of Income as a result of the adoption. Three Months 2018 2017 PPL $ 68 $ 38 PPL Electric 2 (1 ) LKE 2 (2 ) LG&E 1 (2 ) KU 1 (1 )
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement	The following provides a reconciliation of Cash, Cash Equivalents and Restricted Cash reported within the Balance Sheets that sum to the total of the same amounts shown on the Statements of Cash Flows: PPL PPL Electric March 31, 2018 December 31, 2017 March 31, 2018 December 31, 2017 Cash and cash equivalents $ 629 $ 485 $ 20 $ 49 Restricted cash - current (a) 3 3 2 2 Restricted cash - noncurrent (a) 21 23 — — Total Cash, Cash Equivalents and Restricted Cash $ 653 $ 511 $ 22 $ 51 (a) Bank deposits and other cash equivalents that are restricted by agreement or that have been clearly designated for a specific purpose are classified as restricted cash. On the Balance Sheets, the current portion of restricted cash is included in "Other current assets," while the noncurrent portion is included in "Other noncurrent assets."

Segment and Related Informati31

Segment and Related Information (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Segment and Related Information	Income Statement data for the segments and reconciliation to PPL's consolidated results for the periods ended March 31 are as follows: Three Months 2018 2017 Operating Revenues from external customers U.K. Regulated $ 615 $ 568 Kentucky Regulated 872 809 Pennsylvania Regulated 639 573 Corporate and Other — 1 Total $ 2,126 $ 1,951 Net Income U.K. Regulated (a) $ 197 $ 286 Kentucky Regulated 133 95 Pennsylvania Regulated 148 79 Corporate and Other (26 ) (57 ) Total $ 452 $ 403 (a) Includes unrealized gains and losses from hedging foreign currency economic activity. See Note 14 for additional information. The following provides Balance Sheet data for the segments and reconciliation to PPL's consolidated results as of: March 31, December 31, Assets U.K. Regulated (a) $ 17,444 $ 16,813 Kentucky Regulated 14,500 14,468 Pennsylvania Regulated 10,356 10,082 Corporate and Other (b) 88 116 Total $ 42,388 $ 41,479 (a) Includes $12.9 billion and $12.5 billion of net PP&E as of March 31, 2018 and December 31, 2017 . WPD is not subject to accounting for the effects of certain types of regulation as prescribed by GAAP. (b) Primarily consists of unallocated items, including cash, PP&E and the elimination of inter-segment transactions.

Revenue from Contracts with C32

Revenue from Contracts with Customers (Tables)	3 Months Ended
	Mar. 31, 2018
Revenue from Contracts with Customers [Line Items]
Reconciliation of Revenue from Contracts with Customers [Table Text Block]	The following table reconciles "Operating Revenues" included in each Registrant's Statement of Income with revenues generated from contracts with customers for the period ended March 31, 2018. Three Months PPL PPL Electric LKE LG&E KU Operating Revenues (a) $ 2,126 $ 639 $ 872 $ 419 $ 471 Revenues derived from: Alternative revenue programs (b) 32 2 30 14 16 Other (c) (16 ) (4 ) (5 ) (1 ) (4 ) Revenues from Contracts with Customers $ 2,142 $ 637 $ 897 $ 432 $ 483 (a) PPL includes $615 million of revenues from external customers reported by the U.K. Regulated segment. PPL Electric and LKE represent revenues from external customers reported by the Pennsylvania Regulated and Kentucky Regulated segments. See Note 3 for additional information. (b) Alternative revenue programs for PPL Electric include the over/under-collection of its transmission formula rate. Alternative revenue programs for LKE, LG&E and KU include the over/under collection for the ECR and DSM programs as well as LG&E's over/under collection of its GLT program and KU's over/under collection of its generation formula rate. Over-collections of revenue are shown as positive amounts in the table above; under-collections are shown as negative amounts. (c) Represents additional revenues outside the scope of revenues from contracts with customers such as leases and other miscellaneous revenues.
Disaggregation of Revenue [Table Text Block]	The following table shows revenues from contracts with customers disaggregated by customer class for the period ended March 31, 2018 . Three Months PPL PPL Electric LKE LG&E KU Licensed energy suppliers (a) $ 584 $ — $ — $ — $ — Residential 804 408 396 197 199 Commercial 325 98 227 124 103 Industrial 155 13 142 44 98 Other (b) 105 13 68 31 37 Wholesale - municipal 30 — 30 — 30 Wholesale - other (c) 34 — 34 36 16 Transmission 105 105 — — — Revenues from Contracts with Customers $ 2,142 $ 637 $ 897 $ 432 $ 483 (a) Represents customers of WPD. (b) Primarily includes revenues from pole attachments, street lighting and other public authorities. (c) Includes wholesale power and transmission revenues. LG&E and KU amounts include intercompany power sales and transmission revenues, which are eliminated upon consolidation at LKE.
Credit Loss Recognized from Contracts with Customers [Table Text Block]	The following table shows the accounts receivable balances that were impaired for the period ended March 31, 2018 . Three Months PPL $ 10 PPL Electric 7 LKE 2 LG&E 1 KU 1
Contract with Customer, Asset and Liability [Table Text Block]	The following table shows the balances and certain activity of contract liabilities resulting from contracts with customers. PPL PPL Electric LKE LG&E KU Contract liabilities as of December 31, 2017 $ 29 $ 19 $ 8 $ 4 $ 4 Contract liabilities as of March 31, 2018 20 11 7 3 4 Revenue recognized during the period that was included in the opening contract liability balance 17 8 8 4 4

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Basic and Diluted EPS Computations	Reconciliations of the amounts of income and shares of PPL common stock (in thousands) for the periods ended March 31 used in the EPS calculation are: Three Months 2018 2017 Income (Numerator) Net income $ 452 $ 403 Less amounts allocated to participating securities 1 1 Net income available to PPL common shareowners - Basic and Diluted $ 451 $ 402 Shares of Common Stock (Denominator) Weighted-average shares - Basic EPS 694,514 680,882 Add incremental non-participating securities: Share-based payment awards 808 2,202 Weighted-average shares - Diluted EPS 695,322 683,084 Three Months 2018 2017 Basic EPS Net Income available to PPL common shareowners $ 0.65 $ 0.59 Diluted EPS Net Income available to PPL common shareowners $ 0.65 $ 0.59
Common Stock Issuances	For the periods ended March 31 , PPL issued common stock related to stock-based compensation plans and the DRIP as follows (in thousands): Three Months 2018 2017 Stock-based compensation plans (a) 476 887 DRIP 485 445 (a) Includes stock options exercised, vesting of performance units, vesting of restricted stock units and conversion of stock units granted to directors.
Antidilutive Securities Excluded From Diluted EPS	For the periods ended March 31 , the following shares (in thousands) were excluded from the computations of diluted EPS because the effect would have been antidilutive. Three Months 2018 2017 Stock options 230 696 Restricted stock units 20 —

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2018
Income Taxes [Line Items]
Schedule of Effective Income Tax Rate Reconciliation	Reconciliations of income taxes for the periods ended March 31 are as follows. (PPL) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 119 $ 186 Increase (decrease) due to: State income taxes, net of federal income tax benefit 15 13 Valuation allowance adjustments 7 5 Impact of lower U.K. income tax rates relative to U.S. income tax rates (a) (7 ) (48 ) U.S. income tax on foreign earnings - net of foreign tax credit (a) (b) 1 (9 ) Impact of the U.K. Finance Acts (1 ) (3 ) Depreciation and other items not normalized (a) (12 ) (3 ) Interest benefit on U.K. financing entities (5 ) (4 ) Stock-based compensation 1 (3 ) Other (1 ) (5 ) Total increase (decrease) (2 ) (57 ) Total income taxes $ 117 $ 129 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018. (b) Lower income taxes in 2017 primarily due to the tax benefit of accelerated pension contributions made in the first quarter of 2017. The related tax benefit was recognized over the annual period as a result of utilizing an estimated annual effective tax rate. (PPL Electric) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 41 $ 44 Increase (decrease) due to: State income taxes, net of federal income tax benefit 15 8 Depreciation and other items not normalized (a) (7 ) (2 ) Stock-based compensation — (2 ) Total increase (decrease) 8 4 Total income taxes $ 49 $ 48
PPL Electric Utilities Corp [Member]
Income Taxes [Line Items]
Schedule of Effective Income Tax Rate Reconciliation	Reconciliations of income taxes for the periods ended March 31 are as follows. (PPL Electric) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 41 $ 44 Increase (decrease) due to: State income taxes, net of federal income tax benefit 15 8 Depreciation and other items not normalized (a) (7 ) (2 ) Stock-based compensation — (2 ) Other — — Total increase (decrease) 8 4 Total income taxes $ 49 $ 48 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018.
LG And E And KU Energy LLC [Member]
Income Taxes [Line Items]
Schedule of Effective Income Tax Rate Reconciliation	Reconciliations of income taxes for the periods ended March 31 are as follows. (LKE) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 38 $ 58 Increase (decrease) due to: State income taxes, net of federal income tax benefit 8 6 Amortization of investment tax credit — — Stock-based compensation — — Other (2 ) (1 ) Total increase (decrease) 1 5 Total income taxes $ 39 $ 63 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018.
Louisville Gas And Electric Co [Member]
Income Taxes [Line Items]
Schedule of Effective Income Tax Rate Reconciliation	Reconciliations of income taxes for the periods ended March 31 are as follows. (LG&E) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 20 $ 30 Increase (decrease) due to: State income taxes, net of federal income tax benefit 4 3 Other (1 ) — Total increase (decrease) 1 3 Total income taxes $ 21 $ 33 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018.
Kentucky Utilities Co [Member]
Income Taxes [Line Items]
Schedule of Effective Income Tax Rate Reconciliation	Reconciliations of income taxes for the periods ended March 31 are as follows. (KU) Three Months 2018 2017 Federal income tax on Income Before Income Taxes at statutory tax rate (a) $ 23 $ 36 Increase (decrease) due to: State income taxes, net of federal income tax benefit 5 4 Other (1 ) (1 ) Total increase (decrease) 1 3 Total income taxes $ 24 $ 39 (a) The U.S. federal corporate income tax rate was reduced from 35% to 21%, as enacted by the TCJA, effective January 1, 2018.

Utility Rate Regulation (Tables

Utility Rate Regulation (Tables)	3 Months Ended
	Mar. 31, 2018
Utility Rate Regulation [Line Items]
Regulatory Assets and Liabilities	The following table provides information about the regulatory assets and liabilities of cost-based rate-regulated utility operations. PPL PPL Electric March 31, December 31, March 31, December 31, Current Regulatory Assets: Environmental cost recovery $ — $ 5 $ — $ — Generation formula rate 2 6 — — Smart meter rider 15 15 15 15 Plant outage costs 6 3 — — Other 5 5 1 1 Total current regulatory assets (a) $ 28 $ 34 $ 16 $ 16 Noncurrent Regulatory Assets: Defined benefit plans $ 866 $ 880 $ 496 $ 504 Taxes recoverable through future rates 3 3 3 3 Storm costs (b) 47 33 17 — Unamortized loss on debt 51 54 27 29 Interest rate swaps 22 26 — — Terminated interest rate swaps 91 92 — — Accumulated cost of removal of utility plant 176 173 176 173 AROs 247 234 — — Act 129 compliance rider 7 — 7 — Other 9 9 — — Total noncurrent regulatory assets $ 1,519 $ 1,504 $ 726 $ 709 PPL PPL Electric March 31, December 31, March 31, December 31, Current Regulatory Liabilities: Generation supply charge $ 33 $ 34 $ 33 $ 34 Transmission service charge 16 9 16 9 Environmental cost recovery 18 1 — — Universal service rider 24 26 24 26 Transmission formula rate 10 9 10 9 Fuel adjustment clause 2 3 — — TCJA bill credit (c) 34 — — — Storm damage expense rider 12 8 12 8 Other 9 5 — — Total current regulatory liabilities $ 158 $ 95 $ 95 $ 86 Noncurrent Regulatory Liabilities: Accumulated cost of removal of utility plant $ 677 $ 677 $ — $ — Power purchase agreement - OVEC (d) 66 68 — — Net deferred taxes (e) 1,839 1,853 660 668 Defined benefit plans 28 27 — — Terminated interest rate swaps 74 74 — — Other 5 5 2 — Total noncurrent regulatory liabilities $ 2,689 $ 2,704 $ 662 $ 668 LKE LG&E KU March 31, December 31, March 31, December 31, March 31, December 31, Current Regulatory Assets: Environmental cost recovery $ — $ 5 $ — $ 5 $ — $ — Generation formula rate 2 6 — — 2 6 Plant outage costs 6 3 6 3 — — Other 4 4 4 4 — — Total current regulatory assets $ 12 $ 18 $ 10 $ 12 $ 2 $ 6 Noncurrent Regulatory Assets: Defined benefit plans $ 370 $ 376 $ 230 $ 234 $ 140 $ 142 Storm costs 30 33 16 18 14 15 Unamortized loss on debt 24 25 15 16 9 9 Interest rate swaps 22 26 22 26 — — Terminated interest rate swaps 91 92 53 54 38 38 AROs 247 234 67 61 180 173 Other 9 9 3 2 6 7 Total noncurrent regulatory assets $ 793 $ 795 $ 406 $ 411 $ 387 $ 384 LKE LG&E KU March 31, December 31, March 31, December 31, March 31, December 31, Current Regulatory Liabilities: Environmental cost recovery $ 18 $ 1 $ 7 $ — $ 11 $ 1 Fuel adjustment clause 2 3 — — 2 3 Gas line tracker 2 3 2 3 — — TCJA bill credit (c) 34 — 16 — 18 — Other 7 2 4 — 3 2 Total current regulatory liabilities $ 63 $ 9 $ 29 $ 3 $ 34 $ 6 Noncurrent Regulatory Liabilities: Accumulated cost of removal of utility plant $ 677 $ 677 $ 280 $ 282 $ 397 395 Power purchase agreement - OVEC (d) 66 68 46 47 20 21 Net deferred taxes (e) 1,179 1,185 549 552 630 633 Defined benefit plans 28 27 — — 28 27 Terminated interest rate swaps 74 74 37 37 37 37 Other 3 5 — 1 3 4 Total noncurrent regulatory liabilities $ 2,027 $ 2,036 $ 912 $ 919 $ 1,115 $ 1,117 (a) For PPL, these amounts are included in "Other current assets" on the Balance Sheets. (b) Storm costs incurred in PPL Electric's territory from a March 2018 storm will be amortized from 2019 through 2021. (c) Relates to estimated amounts owed to customers as a result of the reduced U.S. federal corporate income tax rate as enacted by the TCJA, effective January 1, 2018, not yet reflected in customer rates. (d) This liability was recorded as an offset to an intangible asset that was recorded at fair value upon the acquisition of LKE by PPL. (e) Primarily relates to excess deferred taxes recorded as a result of the TCJA, which reduced the U.S. federal corporate income tax rate effective January 1, 2018, requiring deferred tax balances and the associated regulatory liabilities to be remeasured as of December 31, 2017.

Financing Activities (Tables)

Financing Activities (Tables)	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Schedule of Line of Credit Facilities	The following credit facilities were in place at: March 31, 2018 December 31, 2017 Expiration Date Capacity Borrowed Letters of Credit and Commercial Paper Issued Unused Capacity Borrowed Letters of Credit and Commercial Paper Issued PPL U.K. WPD plc Syndicated Credit Facility (a) Jan. 2022 £ 210 £ 145 £ — £ 67 £ 148 £ — Term Loan Facility (b) Dec. 2018 130 130 — — — — WPD (South West) Syndicated Credit Facility July 2021 245 — — 245 — — WPD (East Midlands) Syndicated Credit Facility (c) July 2021 300 157 — 143 180 — WPD (West Midlands) Syndicated Credit Facility (d) July 2021 300 65 — 235 120 — Uncommitted Credit Facilities 130 — 4 126 — 4 Total U.K. Credit Facilities (e) £ 1,315 £ 497 £ 4 £ 816 £ 448 £ 4 U.S. PPL Capital Funding Syndicated Credit Facility Jan. 2023 $ 950 $ — $ 345 $ 605 $ — $ 230 Syndicated Credit Facility Nov. 2018 300 — — 300 — — Bilateral Credit Facility Mar. 2019 100 — 24 76 — 18 Total PPL Capital Funding Credit Facilities $ 1,350 $ — $ 369 $ 981 $ — $ 248 PPL Electric Syndicated Credit Facility Jan. 2023 $ 650 $ — $ 214 $ 436 $ — $ 1 LKE Syndicated Credit Facility Oct. 2018 $ 75 $ — $ — $ 75 $ — $ — LG&E Syndicated Credit Facility Jan. 2023 $ 500 $ — $ 137 $ 363 $ — $ 199 Term Loan Credit Facility Oct. 2019 200 200 — — 100 — Total LG&E Credit Facilities $ 700 $ 200 $ 137 $ 363 $ 100 $ 199 KU Syndicated Credit Facility Jan. 2023 $ 400 $ — $ 78 $ 322 $ — $ 45 Letter of Credit Facility Oct. 2020 198 — 198 — — 198 Total KU Credit Facilities $ 598 $ — $ 276 $ 322 $ — $ 243 (a) The amounts borrowed at March 31, 2018 and December 31, 2017 were USD-denominated borrowings of $200 million for both periods, which bore interest at 2.47% and 2.17% . The unused capacity reflects the amount borrowed in GBP of £143 million as of the date borrowed. (b) The amount borrowed at March 31, 2018 was a GBP-denominated borrowing which equated to $179 million and bore interest at 1.77% . (c) The amounts borrowed at March 31, 2018 and December 31, 2017 were GBP-denominated borrowings which equated to $216 million and $244 million and bore interest at 0.90% and 0.89% . (d) The amounts borrowed at March 31, 2018 and December 31, 2017 were GBP-denominated borrowings which equated to $89 million and $162 million and bore interest at 0.90% and 0.89% . (e) At March 31, 2018 , the unused capacity under the U.K. credit facilities was $1.1 billion .
Schedule of Short-term Debt	The following commercial paper programs were in place at: March 31, 2018 December 31, 2017 Weighted - Average Interest Rate Capacity Commercial Paper Issuances Unused Capacity Weighted - Average Interest Rate Commercial Paper Issuances PPL Capital Funding 2.44% $ 1,000 $ 345 $ 655 1.64% $ 230 PPL Electric 2.42% 650 213 437 — LG&E 2.23% 350 137 213 1.83% 199 KU 2.35% 350 78 272 1.97% 45 Total $ 2,350 $ 773 $ 1,577 $ 474

Defined Benefits (Tables)

Defined Benefits (Tables)	3 Months Ended
	Mar. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule Of Net Periodic Defined Benefit Costs (Credits)	Following are the net periodic defined benefit costs (credits) of the plans sponsored by PPL and its subsidiaries, LKE and its subsidiaries, and LG&E for the periods ended March 31 : Pension Benefits Three Months U.S. U.K. 2018 2017 2018 2017 PPL Service cost $ 16 $ 17 $ 21 $ 19 Interest cost 39 42 47 43 Expected return on plan assets (62 ) (57 ) (150 ) (125 ) Amortization of: Prior service cost 2 2 — — Actuarial loss 22 20 39 35 Net periodic defined benefit costs (credits) before settlements and special termination benefits 17 24 (43 ) (28 ) Special termination benefits (a) — 2 — — Net periodic defined benefit costs (credits) $ 17 $ 26 $ (43 ) $ (28 ) (a) Enhanced pension benefits offered to certain PPL Electric bargaining unit employees under a one-time voluntary retirement window offered as part of the new five year IBEW contract ratified in March 2017. Pension Benefits Three Months 2018 2017 LKE Service cost $ 7 $ 7 Interest cost 16 16 Expected return on plan assets (26 ) (22 ) Amortization of: Prior service cost 2 2 Actuarial loss (a) 10 11 Net periodic defined benefit costs $ 9 $ 14 (a) As a result of treatment approved by the KPSC, the difference between actuarial loss calculated in accordance with LKE's accounting policy and actuarial loss calculated using a 15 -year amortization period was $4 million and $5 million for the three months ended March 31, 2018 and 2017. This difference is recorded as a regulatory asset. Pension Benefits Three Months 2018 2017 LG&E Interest cost $ 3 $ 3 Expected return on plan assets (5 ) (5 ) Amortization of: Prior service cost 1 1 Actuarial loss (a) 2 3 Net periodic defined benefit costs $ 1 $ 2 (a) As a result of treatment approved by the KPSC, the difference between actuarial loss calculated in accordance with LG&E's accounting policy and actuarial loss calculated using a 15 -year amortization period was $1 million for the three months ended March 31, 2018 and 2017. This difference is recorded as a regulatory asset. Other Postretirement Benefits Three Months 2018 2017 PPL Service cost $ 1 $ 2 Interest cost 3 6 Expected return on plan assets (4 ) (6 ) Amortization of prior service cost (1 ) — Net periodic defined benefit costs (credits) $ (1 ) $ 2 LKE Service cost $ 1 $ 1 Interest cost 2 2 Expected return on plan assets (2 ) (1 ) Net periodic defined benefit costs $ 1 $ 2
PPL Electric Utilities Corp [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation of Net Periodic Benefit Costs	For the periods ended March 31 , PPL Services allocated the following net periodic defined benefit costs to PPL Electric, and LKE allocated the following net periodic defined benefit costs to LG&E and KU: Three Months 2018 2017 PPL Electric $ 4 $ 8 LG&E 2 3 KU 1 4
LG And E And KU Energy LLC [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule Of Net Periodic Defined Benefit Costs (Credits)	Following are the net periodic defined benefit costs (credits) of the plans sponsored by PPL and its subsidiaries, LKE and its subsidiaries, and LG&E for the periods ended March 31 : Pension Benefits Three Months U.S. U.K. 2018 2017 2018 2017 PPL Service cost $ 16 $ 17 $ 21 $ 19 Interest cost 39 42 47 43 Expected return on plan assets (62 ) (57 ) (150 ) (125 ) Amortization of: Prior service cost 2 2 — — Actuarial loss 22 20 39 35 Net periodic defined benefit costs (credits) before settlements and special termination benefits 17 24 (43 ) (28 ) Special termination benefits (a) — 2 — — Net periodic defined benefit costs (credits) $ 17 $ 26 $ (43 ) $ (28 ) (a) Enhanced pension benefits offered to certain PPL Electric bargaining unit employees under a one-time voluntary retirement window offered as part of the new five year IBEW contract ratified in March 2017. Pension Benefits Three Months 2018 2017 LKE Service cost $ 7 $ 7 Interest cost 16 16 Expected return on plan assets (26 ) (22 ) Amortization of: Prior service cost 2 2 Actuarial loss (a) 10 11 Net periodic defined benefit costs $ 9 $ 14 (a) As a result of treatment approved by the KPSC, the difference between actuarial loss calculated in accordance with LKE's accounting policy and actuarial loss calculated using a 15 -year amortization period was $4 million and $5 million for the three months ended March 31, 2018 and 2017. This difference is recorded as a regulatory asset. Pension Benefits Three Months 2018 2017 LG&E Interest cost $ 3 $ 3 Expected return on plan assets (5 ) (5 ) Amortization of: Prior service cost 1 1 Actuarial loss (a) 2 3 Net periodic defined benefit costs $ 1 $ 2 (a) As a result of treatment approved by the KPSC, the difference between actuarial loss calculated in accordance with LG&E's accounting policy and actuarial loss calculated using a 15 -year amortization period was $1 million for the three months ended March 31, 2018 and 2017. This difference is recorded as a regulatory asset. Other Postretirement Benefits Three Months 2018 2017 PPL Service cost $ 1 $ 2 Interest cost 3 6 Expected return on plan assets (4 ) (6 ) Amortization of prior service cost (1 ) — Net periodic defined benefit costs (credits) $ (1 ) $ 2 LKE Service cost $ 1 $ 1 Interest cost 2 2 Expected return on plan assets (2 ) (1 ) Net periodic defined benefit costs $ 1 $ 2
Louisville Gas And Electric Co [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule Of Net Periodic Defined Benefit Costs (Credits)	Following are the net periodic defined benefit costs (credits) of the plans sponsored by PPL and its subsidiaries, LKE and its subsidiaries, and LG&E for the periods ended March 31 : Pension Benefits Three Months U.S. U.K. 2018 2017 2018 2017 PPL Service cost $ 16 $ 17 $ 21 $ 19 Interest cost 39 42 47 43 Expected return on plan assets (62 ) (57 ) (150 ) (125 ) Amortization of: Prior service cost 2 2 — — Actuarial loss 22 20 39 35 Net periodic defined benefit costs (credits) before settlements and special termination benefits 17 24 (43 ) (28 ) Special termination benefits (a) — 2 — — Net periodic defined benefit costs (credits) $ 17 $ 26 $ (43 ) $ (28 ) (a) Enhanced pension benefits offered to certain PPL Electric bargaining unit employees under a one-time voluntary retirement window offered as part of the new five year IBEW contract ratified in March 2017. Pension Benefits Three Months 2018 2017 LKE Service cost $ 7 $ 7 Interest cost 16 16 Expected return on plan assets (26 ) (22 ) Amortization of: Prior service cost 2 2 Actuarial loss (a) 10 11 Net periodic defined benefit costs $ 9 $ 14 (a) As a result of treatment approved by the KPSC, the difference between actuarial loss calculated in accordance with LKE's accounting policy and actuarial loss calculated using a 15 -year amortization period was $4 million and $5 million for the three months ended March 31, 2018 and 2017. This difference is recorded as a regulatory asset.
Allocation of Net Periodic Benefit Costs	For the periods ended March 31 , PPL Services allocated the following net periodic defined benefit costs to PPL Electric, and LKE allocated the following net periodic defined benefit costs to LG&E and KU: Three Months 2018 2017 PPL Electric $ 4 $ 8 LG&E 2 3 KU 1 4
Kentucky Utilities Co [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation of Net Periodic Benefit Costs	For the periods ended March 31 , PPL Services allocated the following net periodic defined benefit costs to PPL Electric, and LKE allocated the following net periodic defined benefit costs to LG&E and KU: Three Months 2018 2017 PPL Electric $ 4 $ 8 LG&E 2 3 KU 1 4

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Guarantees	The table below details guarantees provided as of March 31, 2018 . Exposure at Expiration PPL Indemnifications related to the WPD Midlands acquisition (a) WPD indemnifications for entities in liquidation and sales of assets $ 11 (b) 2020 WPD guarantee of pension and other obligations of unconsolidated entities 99 (c) PPL Electric Guarantee of inventory value 17 (d) 2020 LKE Indemnification of lease termination and other divestitures 201 (e) 2021 LG&E and KU LG&E and KU guarantee of shortfall related to OVEC (f) (a) Indemnifications related to certain liabilities, including a specific unresolved tax issue and those relating to properties and assets owned by the seller that were transferred to WPD Midlands in connection with the acquisition. A cross indemnity has been received from the seller on the tax issue. The maximum exposure and expiration of these indemnifications cannot be estimated because the maximum potential liability is not capped and the expiration date is not specified in the transaction documents. (b) Indemnification to the liquidators and certain others for existing liabilities or expenses or liabilities arising during the liquidation process. The indemnifications are limited to distributions made from the subsidiary to its parent either prior or subsequent to liquidation or are not explicitly stated in the agreements. The indemnifications generally expire 2 to 7 years subsequent to the date of dissolution of the entities. The exposure noted only includes those cases where the agreements provide for specific limits. In connection with their sales of various businesses, WPD and its affiliates have provided the purchasers with indemnifications that are standard for such transactions, including indemnifications for certain pre-existing liabilities and environmental and tax matters or have agreed to continue their obligations under existing third-party guarantees, either for a set period of time following the transactions or upon the condition that the purchasers make reasonable efforts to terminate the guarantees. Additionally, WPD and its affiliates remain secondarily responsible for lease payments under certain leases that they have assigned to third parties. (c) Relates to certain obligations of discontinued or modified electric associations that were guaranteed at the time of privatization by the participating members. Costs are allocated to the members and can be reallocated if an existing member becomes insolvent. At March 31, 2018 , WPD has recorded an estimated discounted liability for which the expected payment/performance is probable. Neither the expiration date nor the maximum amount of potential payments for certain obligations is explicitly stated in the related agreements, and as a result, the exposure has been estimated. (d) A third party logistics firm provides inventory procurement and fulfillment services. The logistics firm has title to the inventory, however, upon termination of the contracts, PPL Electric has guaranteed to purchase any remaining inventory that has not been used or sold. (e) LKE provides certain indemnifications covering the due and punctual payment, performance and discharge by each party of its respective obligations. The most comprehensive of these guarantees is the LKE guarantee covering operational, regulatory and environmental commitments and indemnifications made by WKE under a 2009 Transaction Termination Agreement. This guarantee has a term of 12 years ending July 2021, and a maximum exposure of $200 million , exclusive of certain items such as government fines and penalties that may exceed the maximum. Another WKE-related LKE guarantee covers other indemnifications related to the purchase price of excess power, has a term expiring in 2023, and a maximum exposure of $100 million . In May 2012, LKE's indemnitee received an unfavorable arbitration panel's decision interpreting this matter. In October 2014, LKE's indemnitee filed a motion for discretionary review with the Kentucky Supreme Court seeking to overturn the arbitration decision, and such motion was denied by the court in September 2015. In September 2015, the counterparty issued a demand letter to LKE's indemnitee. In February 2016, the counterparty filed a complaint in Henderson, Kentucky Circuit Court, seeking an award of damages in the matter. The proceeding is currently in the discovery phase. LKE does not believe appropriate contractual, legal or commercial grounds exist for the claim made. LKE believes its indemnifications in the WKE matter remain subject to various uncertainties, including additional legal and contractual developments, as well as future prices, availability and demand for the subject excess power. Although the parties have conducted certain settlement discussions and reached a settlement in principle to resolve all claims for an aggregate amount within LKE's recorded liability, the ultimate outcomes of the WKE termination-related indemnifications cannot be predicted at this time. Additionally, LKE has indemnified various third parties related to historical obligations for other divested subsidiaries and affiliates. The indemnifications vary by entity and the maximum exposures range from being capped at the sale price to no specified maximum. LKE could be required to perform on these indemnifications in the event of covered losses or liabilities being claimed by an indemnified party. LKE cannot predict the ultimate outcomes of the various indemnification scenarios, but does not expect such outcomes to result in significant losses above the amounts recorded. (f) Pursuant to the OVEC power purchase contract, LG&E and KU are obligated to pay for their share of OVEC's excess debt service, post-retirement and decommissioning costs, as well as any shortfall from amounts included within a demand charge designed and expected to cover these costs over the term of the contract. LKE's proportionate share of OVEC's outstanding debt was $117 million at March 31, 2018 , consisting of LG&E's share of $81 million and KU's share of $36 million . The maximum exposure and the expiration date of these potential obligations are not presently determinable. See "Energy Purchase Commitments" in Note 13 in PPL's, LKE's, LG&E's and KU's 2016 Form 10-K for additional information on the OVEC power purchase contract. In connection with recent credit market related developments at OVEC or certain of its sponsors, such parties, including LG&E and KU, are analyzing certain potential additional credit support actions to preserve OVEC's access to credit markets or mitigate risks or adverse impacts relating thereto, including increased interest costs. The ultimate outcome of these matters, including any potential impact on LG&E's and KU's obligations relating to OVEC debt under the power purchase contract cannot be predicted.

Related Party Transactions (Tab

Related Party Transactions (Tables)	3 Months Ended
	Mar. 31, 2018
PPL Electric Utilities Corp [Member]
Related Party Transactions [Line Items]
Intercompany Support Cost Allocations	PPL Services, PPL EU Services and LKS charged the following amounts for the periods ended March 31 , including amounts applied to accounts that are further distributed between capital and expense on the books of the recipients, based on methods that are believed to be reasonable. Three Months 2018 2017 PPL Electric from PPL Services $ 16 $ 51 LKE from PPL Services 7 6 PPL Electric from PPL EU Services 35 18 LG&E from LKS 38 44 KU from LKS 42 44
LG And E And KU Energy LLC [Member]
Related Party Transactions [Line Items]
Intercompany Support Cost Allocations	PPL Services, PPL EU Services and LKS charged the following amounts for the periods ended March 31 , including amounts applied to accounts that are further distributed between capital and expense on the books of the recipients, based on methods that are believed to be reasonable. Three Months 2018 2017 PPL Electric from PPL Services $ 16 $ 51 LKE from PPL Services 7 6 PPL Electric from PPL EU Services 35 18 LG&E from LKS 38 44 KU from LKS 42 44
Louisville Gas And Electric Co [Member]
Related Party Transactions [Line Items]
Intercompany Support Cost Allocations	PPL Services, PPL EU Services and LKS charged the following amounts for the periods ended March 31 , including amounts applied to accounts that are further distributed between capital and expense on the books of the recipients, based on methods that are believed to be reasonable. Three Months 2018 2017 PPL Electric from PPL Services $ 16 $ 51 LKE from PPL Services 7 6 PPL Electric from PPL EU Services 35 18 LG&E from LKS 38 44 KU from LKS 42 44
Kentucky Utilities Co [Member]
Related Party Transactions [Line Items]
Intercompany Support Cost Allocations	PPL Services, PPL EU Services and LKS charged the following amounts for the periods ended March 31 , including amounts applied to accounts that are further distributed between capital and expense on the books of the recipients, based on methods that are believed to be reasonable. Three Months 2018 2017 PPL Electric from PPL Services $ 16 $ 51 LKE from PPL Services 7 6 PPL Electric from PPL EU Services 35 18 LG&E from LKS 38 44 KU from LKS 42 44

Other Income (Expense)- net Oth

Other Income (Expense)- net Other Income (Expense) - net (Tables)	3 Months Ended
	Mar. 31, 2018
Other Income (Expense) Net [Line Items]
Schedule of Other Nonoperating Income (Expense) [Table Text Block]	The details of "Other Income (Expense) - net" for the three months ended March 31 , were: PPL 2018 2017 Other Income Defined benefit plans - non-service credits (Note 9) $ 68 $ 38 AFUDC - equity component 5 2 Miscellaneous 1 9 Total Other Income 74 49 Other Expense Economic foreign currency exchange contracts (Note 14) 112 43 Charitable contributions 4 4 Miscellaneous 1 11 Total Other Expense 117 58 Other Income (Expense) - net $ (43 ) $ (9 )
PPL Electric Utilities Corp [Member]
Other Income (Expense) Net [Line Items]
Schedule of Other Nonoperating Income (Expense) [Table Text Block]	The details of "Other Income (Expense) - net" for the three months ended March 31 , were: PPL Electric 2018 2017 Other Income AFUDC - equity component $ 5 $ 2 Defined benefit plans - non-service credits (Note 9) 2 — Total Other Income 7 2 Other Expense Charitable contributions 1 1 Defined benefit plans - non-service costs (Note 9) — 1 Total Other Expense 1 2 Other Income (Expense) - net $ 6 $ —

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The assets and liabilities measured at fair value were: March 31, 2018 December 31, 2017 Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 PPL Assets Cash and cash equivalents $ 629 $ 629 $ — $ — $ 485 $ 485 $ — $ — Restricted cash and cash equivalents (a) 24 24 — — 26 26 — — Price risk management assets (b): Foreign currency contracts 97 — 97 — 163 — 163 — Cross-currency swaps 79 — 79 — 101 — 101 — Total price risk management assets 176 — 176 — 264 — 264 — Total assets $ 829 $ 653 $ 176 $ — $ 775 $ 511 $ 264 $ — Liabilities Price risk management liabilities (b): Interest rate swaps $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — Foreign currency contracts 167 — 167 — 148 — 148 — Total price risk management liabilities $ 189 $ — $ 189 $ — $ 174 $ — $ 174 $ — PPL Electric Assets Cash and cash equivalents $ 20 $ 20 $ — $ — $ 49 $ 49 $ — $ — Restricted cash and cash equivalents (a) 2 2 — — 2 2 — — Total assets $ 22 $ 22 $ — $ — $ 51 $ 51 $ — $ — LKE Assets Cash and cash equivalents $ 27 $ 27 $ — $ — $ 30 $ 30 $ — $ — Total assets $ 27 $ 27 $ — $ — $ 30 $ 30 $ — $ — Liabilities Price risk management liabilities: Interest rate swaps $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — Total price risk management liabilities $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — LG&E Assets Cash and cash equivalents $ 14 $ 14 $ — $ — $ 15 $ 15 $ — $ — Total assets $ 14 $ 14 $ — $ — $ 15 $ 15 $ — $ — Liabilities Price risk management liabilities: Interest rate swaps $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — Total price risk management liabilities $ 22 $ — $ 22 $ — $ 26 $ — $ 26 $ — March 31, 2018 December 31, 2017 Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 KU Assets Cash and cash equivalents $ 11 $ 11 $ — $ — $ 15 $ 15 $ — $ — Total assets $ 11 $ 11 $ — $ — $ 15 $ 15 $ — $ — (a) Current portion is included in "Other current assets" and long-term portion is included in "Other noncurrent assets" on the Balance Sheets. (b) Current portion is included in "Price risk management assets" and "Other current liabilities" and noncurrent portion is included in "Price risk management assets" and "Other deferred credits and noncurrent liabilities" on the Balance Sheets.
Fair Value, by Balance Sheet Grouping	The carrying amounts of long-term debt on the Balance Sheets and their estimated fair values are set forth below. March 31, 2018 December 31, 2017 Carrying Fair Value Carrying Fair Value PPL $ 20,464 $ 23,577 $ 20,195 $ 23,783 PPL Electric 3,298 3,632 3,298 3,769 LKE 5,259 5,654 5,159 5,670 LG&E 1,808 1,925 1,709 1,865 KU 2,329 2,546 2,328 2,605 (a) Amounts are net of debt issuance costs.

Derivative Instruments and He42

Derivative Instruments and Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments And Hedging Activities [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents the fair value and location of derivative instruments recorded on the Balance Sheets. March 31, 2018 December 31, 2017 Derivatives designated as hedging instruments Derivatives not designated as hedging instruments Derivatives designated as hedging instruments Derivatives not designated as hedging instruments Assets Liabilities Assets Liabilities Assets Liabilities Assets Liabilities Current: Price Risk Management Assets/Liabilities (a): Interest rate swaps (b) $ — $ — $ — $ 4 $ — $ — $ — $ 4 Cross-currency swaps (b) 4 — — — 4 — — — Foreign currency contracts 1 2 51 75 — — 45 67 Total current 5 2 51 79 4 — 45 71 Noncurrent: Price Risk Management Assets/Liabilities (a): Interest rate swaps (b) — — — 18 — — — 22 Cross-currency swaps (b) 75 — — — 97 — — — Foreign currency contracts — — 45 90 — — 118 81 Total noncurrent 75 — 45 108 97 — 118 103 Total derivatives $ 80 $ 2 $ 96 $ 187 $ 101 $ — $ 163 $ 174 (a) Current portion is included in "Price risk management assets" and "Other current liabilities" and noncurrent portion is included in "Price risk management assets" and "Other deferred credits and noncurrent liabilities" on the Balance Sheets. (b) Excludes accrued interest, if applicable.
Derivative Instruments, Gain (Loss)	The following tables present the pre-tax effect of derivative instruments recognized in income, OCI or regulatory assets and regulatory liabilities for the periods ended March 31, 2018 . Three Months Derivative Derivative Gain (Loss) Recognized in OCI (Effective Portion) Location of Gain (Loss) Gain (Loss) Three Months Cash Flow Hedges: Interest rate swaps $ — Interest expense $ (2 ) $ — Cross-currency swaps (24 ) Other income (expense) - net (12 ) — Total $ (24 ) $ (14 ) $ — Net Investment Hedges: Foreign currency contracts $ (1 ) Derivatives Not Designated as Location of Gain (Loss) Recognized in Hedging Instruments Income on Derivative Three Months Foreign currency contracts Other income (expense) - net $ (112 ) Interest rate swaps Interest expense (1 ) Total $ (113 ) Derivatives Not Designated as Location of Gain (Loss) Recognized as Hedging Instruments Regulatory Liabilities/Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 4 The following tables present the pre-tax effect of derivative instruments recognized in income, OCI or regulatory assets and regulatory liabilities for the periods ended March 31, 2017 . Three Months Derivative Derivative Gain (Loss) Recognized in OCI (Effective Portion) Location of Gain (Loss) Gain (Loss) Three Months Cash Flow Hedges: Interest rate swaps $ — Interest expense $ (2 ) $ (1 ) Cross-currency swaps (8 ) Interest expense 1 — Other income (expense) - net 3 — Total $ (8 ) $ 2 $ (1 ) Net Investment Hedges: Foreign currency contracts $ — Derivatives Not Designated as Location of Gain (Loss) Recognized in Hedging Instruments Income on Derivative Three Months Foreign currency contracts Other income (expense) - net $ (43 ) Interest rate swaps Interest expense (2 ) Total $ (45 ) Derivatives Not Designated as Location of Gain (Loss) Recognized as Hedging Instruments Regulatory Liabilities/Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 2
Derivative Positions Eligible for Offset with Related Cash Collateral	The table below summarizes the derivative positions presented in the balance sheets where a right of setoff exists under these arrangements and related cash collateral received or pledged. Assets Liabilities Eligible for Offset Eligible for Offset Gross Derivative Instruments Cash Collateral Received Net Gross Derivative Instruments Cash Collateral Pledged Net March 31, 2018 Treasury Derivatives PPL $ 176 $ 78 $ 16 $ 82 $ 189 $ 78 $ 5 $ 106 LKE — — — — 22 — — 22 LG&E — — — — 22 — — 22 December 31, 2017 Treasury Derivatives PPL $ 264 $ 107 $ 20 $ 137 $ 174 $ 107 $ — $ 67 LKE — — — — 26 — — 26 LG&E — — — — 26 — — 26
Credit Risk-Related Contingent Features	At March 31, 2018 , derivative contracts in a net liability position that contain credit risk-related contingent features, collateral posted on those positions and the related effect of a decrease in credit ratings below investment grade are summarized as follows: PPL LKE LG&E Aggregate fair value of derivative instruments in a net liability position with credit risk-related contingent features $ 101 $ 8 $ 8 Aggregate fair value of collateral posted on these derivative instruments 10 — — Aggregate fair value of additional collateral requirements in the event of a credit downgrade below investment grade (a) 91 8 8 (a) Includes the effect of net receivables and payables already recorded on the Balance Sheet.
LG And E And KU Energy LLC [Member]
Derivative Instruments And Hedging Activities [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents the fair value and the location on the Balance Sheets of derivatives not designated as hedging instruments. March 31, 2018 December 31, 2017 Assets Liabilities Assets Liabilities Current: Price Risk Management Assets/Liabilities: Interest rate swaps $ — $ 4 $ — $ 4 Total current — 4 — 4 Noncurrent: Price Risk Management Assets/Liabilities: Interest rate swaps — 18 — 22 Total noncurrent — 18 — 22 Total derivatives $ — $ 22 $ — $ 26
Derivative Instruments, Gain (Loss)	The following tables present the pre-tax effect of derivatives not designated as cash flow hedges that are recognized in income or regulatory assets for the periods ended March 31, 2018 . Location of Gain (Loss) Recognized in Derivative Instruments Income on Derivatives Three Months Interest rate swaps Interest expense $ (1 ) Location of Gain (Loss) Recognized in Derivative Instruments Regulatory Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 4 The following tables present the pre-tax effect of derivatives not designated as cash flow hedges that are recognized in income or regulatory assets for the periods ended March 31, 2017 . Location of Gain (Loss) Recognized in Derivative Instruments Income on Derivatives Three Months Interest rate swaps Interest expense $ (2 ) Location of Gain (Loss) Recognized in Derivative Instruments Regulatory Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 2
Derivative Positions Eligible for Offset with Related Cash Collateral	The table below summarizes the derivative positions presented in the balance sheets where a right of setoff exists under these arrangements and related cash collateral received or pledged. Assets Liabilities Eligible for Offset Eligible for Offset Gross Derivative Instruments Cash Collateral Received Net Gross Derivative Instruments Cash Collateral Pledged Net March 31, 2018 Treasury Derivatives PPL $ 176 $ 78 $ 16 $ 82 $ 189 $ 78 $ 5 $ 106 LKE — — — — 22 — — 22 LG&E — — — — 22 — — 22 December 31, 2017 Treasury Derivatives PPL $ 264 $ 107 $ 20 $ 137 $ 174 $ 107 $ — $ 67 LKE — — — — 26 — — 26 LG&E — — — — 26 — — 26
Credit Risk-Related Contingent Features	At March 31, 2018 , derivative contracts in a net liability position that contain credit risk-related contingent features, collateral posted on those positions and the related effect of a decrease in credit ratings below investment grade are summarized as follows: PPL LKE LG&E Aggregate fair value of derivative instruments in a net liability position with credit risk-related contingent features $ 101 $ 8 $ 8 Aggregate fair value of collateral posted on these derivative instruments 10 — — Aggregate fair value of additional collateral requirements in the event of a credit downgrade below investment grade (a) 91 8 8 (a) Includes the effect of net receivables and payables already recorded on the Balance Sheet.
Louisville Gas And Electric Co [Member]
Derivative Instruments And Hedging Activities [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents the fair value and the location on the Balance Sheets of derivatives not designated as hedging instruments. March 31, 2018 December 31, 2017 Assets Liabilities Assets Liabilities Current: Price Risk Management Assets/Liabilities: Interest rate swaps $ — $ 4 $ — $ 4 Total current — 4 — 4 Noncurrent: Price Risk Management Assets/Liabilities: Interest rate swaps — 18 — 22 Total noncurrent — 18 — 22 Total derivatives $ — $ 22 $ — $ 26
Derivative Instruments, Gain (Loss)	The following tables present the pre-tax effect of derivatives not designated as cash flow hedges that are recognized in income or regulatory assets for the periods ended March 31, 2018 . Location of Gain (Loss) Recognized in Derivative Instruments Income on Derivatives Three Months Interest rate swaps Interest expense $ (1 ) Location of Gain (Loss) Recognized in Derivative Instruments Regulatory Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 4 The following tables present the pre-tax effect of derivatives not designated as cash flow hedges that are recognized in income or regulatory assets for the periods ended March 31, 2017 . Location of Gain (Loss) Recognized in Derivative Instruments Income on Derivatives Three Months Interest rate swaps Interest expense $ (2 ) Location of Gain (Loss) Recognized in Derivative Instruments Regulatory Assets Three Months Interest rate swaps Regulatory assets - noncurrent $ 2
Derivative Positions Eligible for Offset with Related Cash Collateral	The table below summarizes the derivative positions presented in the balance sheets where a right of setoff exists under these arrangements and related cash collateral received or pledged. Assets Liabilities Eligible for Offset Eligible for Offset Gross Derivative Instruments Cash Collateral Received Net Gross Derivative Instruments Cash Collateral Pledged Net March 31, 2018 Treasury Derivatives PPL $ 176 $ 78 $ 16 $ 82 $ 189 $ 78 $ 5 $ 106 LKE — — — — 22 — — 22 LG&E — — — — 22 — — 22 December 31, 2017 Treasury Derivatives PPL $ 264 $ 107 $ 20 $ 137 $ 174 $ 107 $ — $ 67 LKE — — — — 26 — — 26 LG&E — — — — 26 — — 26
Credit Risk-Related Contingent Features	At March 31, 2018 , derivative contracts in a net liability position that contain credit risk-related contingent features, collateral posted on those positions and the related effect of a decrease in credit ratings below investment grade are summarized as follows: PPL LKE LG&E Aggregate fair value of derivative instruments in a net liability position with credit risk-related contingent features $ 101 $ 8 $ 8 Aggregate fair value of collateral posted on these derivative instruments 10 — — Aggregate fair value of additional collateral requirements in the event of a credit downgrade below investment grade (a) 91 8 8 (a) Includes the effect of net receivables and payables already recorded on the Balance Sheet.

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	3 Months Ended
	Mar. 31, 2018
Asset Retirement Obligation [Line Items]
Asset Retirement Obligation Roll Forward	The changes in the carrying amounts of AROs were as follows. PPL LKE LG&E KU Balance at December 31, 2017 $ 397 $ 356 $ 121 $ 235 Accretion 3 3 — 3 Effect of foreign exchange rates 1 — — — Changes in estimated timing or cost (a) (10 ) (10 ) (5 ) (5 ) Obligations settled (9 ) (9 ) (5 ) (4 ) Balance at March 31, 2018 $ 382 $ 340 $ 111 $ 229 (a) LG&E and KU recorded decreases to the existing AROs during the three months ended March 31, 2018 primarily related to the closure of CCR impoundments and associated groundwater monitoring. These revisions are the result of changes in closure plans related to expected costs and timing of closures. Further changes to AROs, capital plans or operating costs may be required as estimates of future cash flows are refined based on closure developments and regulatory or legal proceedings.
LG And E And KU Energy LLC [Member]
Asset Retirement Obligation [Line Items]
Asset Retirement Obligation Roll Forward	The changes in the carrying amounts of AROs were as follows. PPL LKE LG&E KU Balance at December 31, 2017 $ 397 $ 356 $ 121 $ 235 Accretion 3 3 — 3 Effect of foreign exchange rates 1 — — — Changes in estimated timing or cost (a) (10 ) (10 ) (5 ) (5 ) Obligations settled (9 ) (9 ) (5 ) (4 ) Balance at March 31, 2018 $ 382 $ 340 $ 111 $ 229 (a) LG&E and KU recorded decreases to the existing AROs during the three months ended March 31, 2018 primarily related to the closure of CCR impoundments and associated groundwater monitoring. These revisions are the result of changes in closure plans related to expected costs and timing of closures. Further changes to AROs, capital plans or operating costs may be required as estimates of future cash flows are refined based on closure developments and regulatory or legal proceedings.
Louisville Gas And Electric Co [Member]
Asset Retirement Obligation [Line Items]
Asset Retirement Obligation Roll Forward	The changes in the carrying amounts of AROs were as follows. PPL LKE LG&E KU Balance at December 31, 2017 $ 397 $ 356 $ 121 $ 235 Accretion 3 3 — 3 Effect of foreign exchange rates 1 — — — Changes in estimated timing or cost (a) (10 ) (10 ) (5 ) (5 ) Obligations settled (9 ) (9 ) (5 ) (4 ) Balance at March 31, 2018 $ 382 $ 340 $ 111 $ 229 (a) LG&E and KU recorded decreases to the existing AROs during the three months ended March 31, 2018 primarily related to the closure of CCR impoundments and associated groundwater monitoring. These revisions are the result of changes in closure plans related to expected costs and timing of closures. Further changes to AROs, capital plans or operating costs may be required as estimates of future cash flows are refined based on closure developments and regulatory or legal proceedings.
Kentucky Utilities Co [Member]
Asset Retirement Obligation [Line Items]
Asset Retirement Obligation Roll Forward	The changes in the carrying amounts of AROs were as follows. PPL LKE LG&E KU Balance at December 31, 2017 $ 397 $ 356 $ 121 $ 235 Accretion 3 3 — 3 Effect of foreign exchange rates 1 — — — Changes in estimated timing or cost (a) (10 ) (10 ) (5 ) (5 ) Obligations settled (9 ) (9 ) (5 ) (4 ) Balance at March 31, 2018 $ 382 $ 340 $ 111 $ 229 (a) LG&E and KU recorded decreases to the existing AROs during the three months ended March 31, 2018 primarily related to the closure of CCR impoundments and associated groundwater monitoring. These revisions are the result of changes in closure plans related to expected costs and timing of closures. Further changes to AROs, capital plans or operating costs may be required as estimates of future cash flows are refined based on closure developments and regulatory or legal proceedings.

Accumulated Other Comprehensi44

Accumulated Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Schedule of Accumulated Other Comprehensive Income (Loss)	The after-tax changes in AOCI by component for the periods ended March 31 were as follows. Foreign currency translation adjustments Unrealized gains (losses) on qualifying derivatives Defined benefit plans Equity investees' AOCI Prior service costs Actuarial gain (loss) Total PPL December 31, 2017 $ (1,089 ) $ (13 ) $ — $ (7 ) $ (2,313 ) $ (3,422 ) Amounts arising during the period 116 (20 ) — — (1 ) 95 Reclassifications from AOCI — 12 — — 36 48 Net OCI during the period 116 (8 ) — — 35 143 March 31, 2018 $ (973 ) $ (21 ) $ — $ (7 ) $ (2,278 ) $ (3,279 ) December 31, 2016 $ (1,627 ) $ (7 ) $ (1 ) $ (8 ) $ (2,135 ) $ (3,778 ) Amounts arising during the period (24 ) (6 ) — — — (30 ) Reclassifications from AOCI — (1 ) — — 32 31 Net OCI during the period (24 ) (7 ) — — 32 1 March 31, 2017 $ (1,651 ) $ (14 ) $ (1 ) $ (8 ) $ (2,103 ) $ (3,777 )
Reclassification out of Other Comprehensive Income (Loss)	The following table presents the gains (losses) and related income taxes for reclassifications from AOCI for the periods ended March 31 . Three Months Affected Line Item on the Details about AOCI 2018 2017 Statements of Income Qualifying derivatives Interest rate swaps $ (2 ) $ (3 ) Interest Expense Cross-currency swaps (12 ) 3 Other Income (Expense) - net — 1 Interest Expense Total Pre-tax (14 ) 1 Income Taxes 2 — Total After-tax (12 ) 1 Equity investees' AOCI — — Other Income (Expense) - net Total Pre-tax — — Income Taxes — — Total After-tax — — Defined benefit plans Prior service costs — — Net actuarial loss (45 ) (41 ) Total Pre-tax (45 ) (41 ) Income Taxes 9 9 Total After-tax (36 ) (32 ) Total reclassifications during the period $ (48 ) $ (31 )

Summary of Significant Accoun45

Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	$ 629		$ 485
Restricted Cash, Current	3		3
Restricted Cash, Noncurrent	21		23
Cash, Cash Equivalents and Restricted Cash	653	$ 433	511	$ 367
Income Statement impact of ASU 2017-07 [Member]
Summary Of Significant Accounting Policies [Line Items]
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit- Non Service	5
Defined Benefit Plan Net Periodic Benefit (Cost) Credit Non Service, After tax	$ 4
Defined Benefit Plan Net Periodic Benefit (Cost) Credit NonService, Per Share	$ 0.01
Impact of adoption of ASU 2017-07 [Member]
Summary Of Significant Accounting Policies [Line Items]
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit- Non Service	$ 68	38
PPL Electric Utilities Corp [Member]
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	20		49
Restricted Cash, Current	2		2
Restricted Cash, Noncurrent	0		0
Cash, Cash Equivalents and Restricted Cash	22	22	51	15
PPL Electric Utilities Corp [Member] | Impact of adoption of ASU 2017-07 [Member]
Summary Of Significant Accounting Policies [Line Items]
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit- Non Service	2	(1)
LG And E And KU Energy LLC [Member]
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	27	15	30	13
LG And E And KU Energy LLC [Member] | Impact of adoption of ASU 2017-07 [Member]
Summary Of Significant Accounting Policies [Line Items]
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit- Non Service	2	(2)
Louisville Gas And Electric Co [Member]
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	14	4	15	5
Louisville Gas And Electric Co [Member] | Impact of adoption of ASU 2017-07 [Member]
Summary Of Significant Accounting Policies [Line Items]
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit- Non Service	1	(2)
Kentucky Utilities Co [Member]
Reconciliation of Cash, Cash Equivalents and Restricted Cash from the Balance Sheet to Cash Flow Statement [Line Items]
Cash and cash equivalents	11	7	$ 15	$ 7
Kentucky Utilities Co [Member] | Impact of adoption of ASU 2017-07 [Member]
Summary Of Significant Accounting Policies [Line Items]
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit- Non Service	$ 1	$ (1)

Segment and Related Informati46

Segment and Related Information (Details) $ in Millions		3 Months Ended
		Mar. 31, 2018USD ($)Integer	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)
Income Statement Data [Abstract]
Operating Revenues from external customers		$ 2,126	$ 1,951
Net Income		452	403
Balance Sheet Data [Abstract]
Assets		42,388		$ 41,479
PPL Electric Utilities Corp [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		639	573
Net Income	[1]	148	79
Balance Sheet Data [Abstract]
Assets		$ 10,343		10,082
Segment (Numeric) [Abstract]
Number of Reportable Segments | Integer		1
Number of Operating Segments | Integer		2
LG And E And KU Energy LLC [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		$ 872	809
Net Income	[2]	142	103
Balance Sheet Data [Abstract]
Assets		$ 14,834		14,802
Segment (Numeric) [Abstract]
Number of Reportable Segments | Integer		1
Number of Operating Segments | Integer		1
Louisville Gas And Electric Co [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		$ 419	391
Net Income	[1]	72	54
Balance Sheet Data [Abstract]
Assets		$ 6,587		6,559
Segment (Numeric) [Abstract]
Number of Reportable Segments | Integer		1
Number of Operating Segments | Integer		1
Kentucky Utilities Co [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		$ 471	437
Net Income	[2]	87	63
Balance Sheet Data [Abstract]
Assets		$ 8,276		8,254
Segment (Numeric) [Abstract]
Number of Reportable Segments | Integer		1
Number of Operating Segments | Integer		1
United Kingdom Regulated [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		$ 615	568
Net Income		197	286
Balance Sheet Data [Abstract]
Assets		17,444		16,813
Segment (Numeric) [Abstract]
Net property, plant and equipment not subject to accounting for the effects of certain types of regulation		12,900		12,500
Kentucky Regulated [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		872	809
Net Income		133	95
Balance Sheet Data [Abstract]
Assets		14,500		14,468
Kentucky Regulated [Member] | LG And E And KU Energy LLC [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		872
Pennsylvania Regulated [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		639	573
Net Income		148	79
Balance Sheet Data [Abstract]
Assets		10,356		10,082
Pennsylvania Regulated [Member] | PPL Electric Utilities Corp [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		639
Corporate And Other [Member]
Income Statement Data [Abstract]
Operating Revenues from external customers		0	1
Net Income		(26)	$ (57)
Balance Sheet Data [Abstract]
Assets		$ 88		$ 116
[1]	Net income equals comprehensive income.
[2]	Net income approximates comprehensive income.

Revenue from Contracts with C47

Revenue from Contracts with Customers (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)Days	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)
Revenue from Contracts with Customers [Line Items]
Operating Revenues	$ 2,126	$ 1,951
Reconciliation of Revenue from Contracts with Customers [Abstract]
Alternative Revenue Programs	32
Other Revenue	(16)
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	2,142
Credit Loss from Contracts with Customers [Abstract]
Provision for Doubtful Accounts	10
Contract with Customer, Asset and Liability [Abstract]
Contract with Customer, Liability	20		$ 29
Contract with Customer, Liability, Revenue Recognized	17
Licensed energy suppliers [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	584
Residential [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	804
Commercial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	325
Industrial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	155
Other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	105
Wholesale - municipal [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	30
Wholesale - other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	34
Transmission [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	105
Pennsylvania Regulated [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	$ 639	573
Number Of Days Due From Invoice Date | Days	21
United Kingdom Regulated [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	$ 615	568
Number Of Days Due From Invoice Date | Days	14
Kentucky Regulated [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	$ 872	809
Number Of Days Due From Invoice Date | Days	22
PPL Electric [Member]
Revenue from Contracts with Customers [Line Items]
Number Of Days Due From Invoice Date | Days	21
LGE [Member]
Revenue from Contracts with Customers [Line Items]
Number Of Days Due From Invoice Date | Days	22
KU [Member]
Revenue from Contracts with Customers [Line Items]
Number Of Days Due From Invoice Date | Days	22
PPL Electric Utilities Corp [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	$ 639	573
Number Of Days Due From Invoice Date | Days	21
Reconciliation of Revenue from Contracts with Customers [Abstract]
Alternative Revenue Programs	$ 2
Other Revenue	(4)
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	637
Credit Loss from Contracts with Customers [Abstract]
Provision for Doubtful Accounts	7
Contract with Customer, Asset and Liability [Abstract]
Contract with Customer, Liability	11		19
Contract with Customer, Liability, Revenue Recognized	8
PPL Electric Utilities Corp [Member] | Licensed energy suppliers [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
PPL Electric Utilities Corp [Member] | Residential [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	408
PPL Electric Utilities Corp [Member] | Commercial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	98
PPL Electric Utilities Corp [Member] | Industrial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	13
PPL Electric Utilities Corp [Member] | Other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	13
PPL Electric Utilities Corp [Member] | Wholesale - municipal [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
PPL Electric Utilities Corp [Member] | Wholesale - other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
PPL Electric Utilities Corp [Member] | Distribution [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	532
PPL Electric Utilities Corp [Member] | Transmission [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	105
PPL Electric Utilities Corp [Member] | Pennsylvania Regulated [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	639
LG And E And KU Energy LLC [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	872	809
Reconciliation of Revenue from Contracts with Customers [Abstract]
Alternative Revenue Programs	30
Other Revenue	(5)
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	897
Credit Loss from Contracts with Customers [Abstract]
Provision for Doubtful Accounts	2
Contract with Customer, Asset and Liability [Abstract]
Contract with Customer, Liability	7		8
Contract with Customer, Liability, Revenue Recognized	8
LG And E And KU Energy LLC [Member] | Licensed energy suppliers [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
LG And E And KU Energy LLC [Member] | Residential [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	396
LG And E And KU Energy LLC [Member] | Commercial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	227
LG And E And KU Energy LLC [Member] | Industrial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	142
LG And E And KU Energy LLC [Member] | Other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	68
LG And E And KU Energy LLC [Member] | Wholesale - municipal [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	30
LG And E And KU Energy LLC [Member] | Wholesale - other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	34
LG And E And KU Energy LLC [Member] | Transmission [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
LG And E And KU Energy LLC [Member] | Kentucky Regulated [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	$ 872
LG And E And KU Energy LLC [Member] | KU [Member]
Revenue from Contracts with Customers [Line Items]
Number Of Days Due From Invoice Date | Days	22
Louisville Gas And Electric Co [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	$ 419	391
Number Of Days Due From Invoice Date | Days	22
Reconciliation of Revenue from Contracts with Customers [Abstract]
Alternative Revenue Programs	$ 14
Other Revenue	(1)
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	432
Credit Loss from Contracts with Customers [Abstract]
Provision for Doubtful Accounts	1
Contract with Customer, Asset and Liability [Abstract]
Contract with Customer, Liability	3		4
Contract with Customer, Liability, Revenue Recognized	4
Louisville Gas And Electric Co [Member] | Licensed energy suppliers [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
Louisville Gas And Electric Co [Member] | Residential [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	197
Louisville Gas And Electric Co [Member] | Commercial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	124
Louisville Gas And Electric Co [Member] | Industrial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	44
Louisville Gas And Electric Co [Member] | Other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	31
Louisville Gas And Electric Co [Member] | Wholesale - municipal [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
Louisville Gas And Electric Co [Member] | Wholesale - other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	36
Louisville Gas And Electric Co [Member] | Transmission [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
Kentucky Utilities Co [Member]
Revenue from Contracts with Customers [Line Items]
Operating Revenues	$ 471	$ 437
Number Of Days Due From Invoice Date | Days	22
Reconciliation of Revenue from Contracts with Customers [Abstract]
Alternative Revenue Programs	$ 16
Other Revenue	(4)
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	483
Credit Loss from Contracts with Customers [Abstract]
Provision for Doubtful Accounts	1
Contract with Customer, Asset and Liability [Abstract]
Contract with Customer, Liability	4		$ 4
Contract with Customer, Liability, Revenue Recognized	4
Kentucky Utilities Co [Member] | Licensed energy suppliers [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	0
Kentucky Utilities Co [Member] | Residential [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	199
Kentucky Utilities Co [Member] | Commercial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	103
Kentucky Utilities Co [Member] | Industrial [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	98
Kentucky Utilities Co [Member] | Other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	37
Kentucky Utilities Co [Member] | Wholesale - municipal [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	30
Kentucky Utilities Co [Member] | Wholesale - other [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	16
Kentucky Utilities Co [Member] | Transmission [Member]
Disaggregation of Revenue [Abstract]
Revenue from Contracts with Customers	$ 0

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income (Numerator) [Abstract]
Net Income	$ 452	$ 403
Less amounts allocated to participating securities	1	1
Net income available to PPL common shareowners - Basic	451	402
Net income available to PPL common shareowners - Diluted	$ 451	$ 402
Shares of Common Stock (Denominator) [Abstract]
Weighted-average shares - Basic EPS (in shares)	694,514	680,882
Add incremental non-participating securities: [Abstract]
Share-based payment awards (in shares)	808	2,202
Weighted-average shares - Diluted EPS (in shares)	695,322	683,084
Basic EPS - Available to PPL common shareowners: [Abstract]
Net Income Available to PPL common shareowners (in dollars per share)	$ 0.65	$ 0.59
Diluted EPS - Available to PPL common shareowners: [Abstract]
Net Income Available to PPL common shareowners (in dollars per share)	$ 0.65	$ 0.59
Shares Issued (Numeric) [Abstract]
Common stock issued under stock-based compensation plans (in shares)	476	887
Common stock issued under dividend reinvestment plan (in shares)	485	445
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computations of diluted EPS	230	696
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computations of diluted EPS	20	0

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	Apr. 13, 2018	Mar. 31, 2018	Mar. 31, 2017
Income Taxes [Line Items]
Increase (Decrease) in Regulatory Assets and Liabilities		$ (64)	$ 17
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate		119	186
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit		15	13
Valuation allowance adjustments		7	5
Impact of lower U.K. income tax rates relative to U.S. income tax rates		(7)	(48)
U.S. income tax on foreign earnings - net of foreign tax credit		1	(9)
Impact of the U.K. Finance Acts		(1)	(3)
Depreciation and other items not normalized		(12)	(3)
Interest benefit on U.K. financing entities		(5)	(4)
Stock-based compensation		1	(3)
Other		(1)	(5)
Total increase (decrease)		(2)	(57)
Total income taxes		117	129
LKE [Member] | Tax Cuts And Jobs Act [Member] | Subsequent Event [Member]
Income Taxes [Line Items]
Deferred Income Tax Expense (Benefit)	$ 9
LGE [Member] | Kentucky tax reform [Member] | Subsequent Event [Member]
Income Taxes [Line Items]
Increase (Decrease) in Regulatory Assets and Liabilities	16
KU [Member] | Kentucky tax reform [Member] | Subsequent Event [Member]
Income Taxes [Line Items]
Increase (Decrease) in Regulatory Assets and Liabilities	19
PPL Electric Utilities Corp [Member]
Income Taxes [Line Items]
Increase (Decrease) in Regulatory Assets and Liabilities		(5)	11
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate		41	44
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit		15	8
Depreciation and other items not normalized		(7)	(2)
Stock-based compensation		0	(2)
Other		0	0
Total increase (decrease)		8	4
Total income taxes		49	48
LG And E And KU Energy LLC [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate		38	58
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit		8	6
Amortization of investment tax credit		0	0
Depreciation and other items not normalized		(5)	0
Stock-based compensation		0	0
Other		(2)	(1)
Total increase (decrease)		1	5
Total income taxes		39	63
LG And E And KU Energy LLC [Member] | Kentucky tax reform [Member] | Subsequent Event [Member]
Income Taxes [Line Items]
Deferred Income Tax Expense (Benefit)	9
LG And E And KU Energy LLC [Member] | LGE [Member] | Kentucky tax reform [Member] | Subsequent Event [Member]
Income Taxes [Line Items]
Increase (Decrease) in Regulatory Assets and Liabilities	16
LG And E And KU Energy LLC [Member] | KU [Member] | Kentucky tax reform [Member] | Subsequent Event [Member]
Income Taxes [Line Items]
Increase (Decrease) in Regulatory Assets and Liabilities	19
Louisville Gas And Electric Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate		20	30
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit		4	3
Depreciation and other items not normalized		(2)	0
Other		(1)	0
Total increase (decrease)		1	3
Total income taxes		21	33
Louisville Gas And Electric Co [Member] | Kentucky tax reform [Member] | Subsequent Event [Member]
Income Taxes [Line Items]
Increase (Decrease) in Regulatory Assets and Liabilities	16
Kentucky Utilities Co [Member]
Reconciliation of Income Tax Expense [Abstract]
Federal income tax on Income Before Income Taxes at statutory tax rate		23	36
Increase (decrease) due to: [Abstract]
State income taxes, net of federal income tax benefit		5	4
Depreciation and other items not normalized		(3)	0
Other		(1)	(1)
Total increase (decrease)		1	3
Total income taxes		$ 24	$ 39
Kentucky Utilities Co [Member] | Kentucky tax reform [Member] | Subsequent Event [Member]
Income Taxes [Line Items]
Increase (Decrease) in Regulatory Assets and Liabilities	$ 19

Utility Rate Regulation - Regul

Utility Rate Regulation - Regulatory Assets (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Regulatory Assets [Line Items]
Current regulatory assets	$ 28	$ 34
Noncurrent regulatory assets	1,519	1,504
Environmental Cost Recovery [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	5
Generation Formula Rate [Member]
Regulatory Assets [Line Items]
Current regulatory assets	2	6
Smart Meter Rider [Member]
Regulatory Assets [Line Items]
Current regulatory assets	15	15
Act 129 Compliance Rider [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	7	0
Defined Benefit Plans [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	866	880
Taxes Recoverable Through Future Rates [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	3	3
Storm Costs [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	47	33
Unamortized Loss On Debt [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	51	54
Interest Rate Swaps [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	22	26
Terminated Interest Rate Swap [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	91	92
Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	176	173
Asset Retirement Obligations [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	247	234
Plant outage costs [Member]
Regulatory Assets [Line Items]
Current regulatory assets	6	3
Other Regulatory Assets [Member]
Regulatory Assets [Line Items]
Current regulatory assets	5	5
Noncurrent regulatory assets	9	9
PPL Electric Utilities Corp [Member]
Regulatory Assets [Line Items]
Current regulatory assets	16	16
Noncurrent regulatory assets	726	709
PPL Electric Utilities Corp [Member] | Environmental Cost Recovery [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	0
PPL Electric Utilities Corp [Member] | Generation Formula Rate [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	0
PPL Electric Utilities Corp [Member] | Smart Meter Rider [Member]
Regulatory Assets [Line Items]
Current regulatory assets	15	15
PPL Electric Utilities Corp [Member] | Act 129 Compliance Rider [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	7	0
PPL Electric Utilities Corp [Member] | Defined Benefit Plans [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	496	504
PPL Electric Utilities Corp [Member] | Taxes Recoverable Through Future Rates [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	3	3
PPL Electric Utilities Corp [Member] | Storm Costs [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	17	0
PPL Electric Utilities Corp [Member] | Unamortized Loss On Debt [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	27	29
PPL Electric Utilities Corp [Member] | Interest Rate Swaps [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	0	0
PPL Electric Utilities Corp [Member] | Terminated Interest Rate Swap [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	0	0
PPL Electric Utilities Corp [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	176	173
PPL Electric Utilities Corp [Member] | Asset Retirement Obligations [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	0	0
PPL Electric Utilities Corp [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	0
PPL Electric Utilities Corp [Member] | Other Regulatory Assets [Member]
Regulatory Assets [Line Items]
Current regulatory assets	1	1
Noncurrent regulatory assets	0	0
LG And E And KU Energy LLC [Member]
Regulatory Assets [Line Items]
Current regulatory assets	12	18
Noncurrent regulatory assets	793	795
LG And E And KU Energy LLC [Member] | Environmental Cost Recovery [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	5
LG And E And KU Energy LLC [Member] | Generation Formula Rate [Member]
Regulatory Assets [Line Items]
Current regulatory assets	2	6
LG And E And KU Energy LLC [Member] | Defined Benefit Plans [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	370	376
LG And E And KU Energy LLC [Member] | Storm Costs [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	30	33
LG And E And KU Energy LLC [Member] | Unamortized Loss On Debt [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	24	25
LG And E And KU Energy LLC [Member] | Interest Rate Swaps [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	22	26
LG And E And KU Energy LLC [Member] | Terminated Interest Rate Swap [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	91	92
LG And E And KU Energy LLC [Member] | Asset Retirement Obligations [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	247	234
LG And E And KU Energy LLC [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current regulatory assets	6	3
LG And E And KU Energy LLC [Member] | Other Regulatory Assets [Member]
Regulatory Assets [Line Items]
Current regulatory assets	4	4
Noncurrent regulatory assets	9	9
Louisville Gas And Electric Co [Member]
Regulatory Assets [Line Items]
Current regulatory assets	10	12
Noncurrent regulatory assets	406	411
Louisville Gas And Electric Co [Member] | Environmental Cost Recovery [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	5
Louisville Gas And Electric Co [Member] | Generation Formula Rate [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	0
Louisville Gas And Electric Co [Member] | Defined Benefit Plans [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	230	234
Louisville Gas And Electric Co [Member] | Storm Costs [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	16	18
Louisville Gas And Electric Co [Member] | Unamortized Loss On Debt [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	15	16
Louisville Gas And Electric Co [Member] | Interest Rate Swaps [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	22	26
Louisville Gas And Electric Co [Member] | Terminated Interest Rate Swap [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	53	54
Louisville Gas And Electric Co [Member] | Asset Retirement Obligations [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	67	61
Louisville Gas And Electric Co [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current regulatory assets	6	3
Louisville Gas And Electric Co [Member] | Other Regulatory Assets [Member]
Regulatory Assets [Line Items]
Current regulatory assets	4	4
Noncurrent regulatory assets	3	2
Kentucky Utilities Co [Member]
Regulatory Assets [Line Items]
Current regulatory assets	2	6
Noncurrent regulatory assets	387	384
Kentucky Utilities Co [Member] | Environmental Cost Recovery [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	0
Kentucky Utilities Co [Member] | Generation Formula Rate [Member]
Regulatory Assets [Line Items]
Current regulatory assets	2	6
Kentucky Utilities Co [Member] | Defined Benefit Plans [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	140	142
Kentucky Utilities Co [Member] | Storm Costs [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	14	15
Kentucky Utilities Co [Member] | Unamortized Loss On Debt [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	9	9
Kentucky Utilities Co [Member] | Interest Rate Swaps [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	0	0
Kentucky Utilities Co [Member] | Terminated Interest Rate Swap [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	38	38
Kentucky Utilities Co [Member] | Asset Retirement Obligations [Member]
Regulatory Assets [Line Items]
Noncurrent regulatory assets	180	173
Kentucky Utilities Co [Member] | Plant outage costs [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	0
Kentucky Utilities Co [Member] | Other Regulatory Assets [Member]
Regulatory Assets [Line Items]
Current regulatory assets	0	0
Noncurrent regulatory assets	$ 6	$ 7

Utility Rate Regulation - Reg51

Utility Rate Regulation - Regulatory Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Regulatory Liabilities [Line Items]
Current regulatory liabilities	$ 158	$ 95
Noncurrent regulatory liabilities	2,689	2,704
Environmental Cost Recovery [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	18	1
Generation Supply Charge [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	33	34
Transmission Service Charge [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	16	9
Universal Service Rider [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	24	26
Transmission Formula Rate [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	10	9
Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	2	3
Storm Damage Expense Rider [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	12	8
Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	677	677
Power Purchase Agreement OVEC [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	66	68
Net deferred taxes [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	1,839	1,853
Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	28	27
Terminated interest rate swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	74	74
TCJA bill credit [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	34	0
Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	9	5
Noncurrent regulatory liabilities	5	5
PPL Electric Utilities Corp [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	95	86
Noncurrent regulatory liabilities	662	668
PPL Electric Utilities Corp [Member] | Environmental Cost Recovery [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	0	0
PPL Electric Utilities Corp [Member] | Generation Supply Charge [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	33	34
PPL Electric Utilities Corp [Member] | Transmission Service Charge [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	16	9
PPL Electric Utilities Corp [Member] | Universal Service Rider [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	24	26
PPL Electric Utilities Corp [Member] | Transmission Formula Rate [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	10	9
PPL Electric Utilities Corp [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	0	0
PPL Electric Utilities Corp [Member] | Storm Damage Expense Rider [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	12	8
PPL Electric Utilities Corp [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	0	0
PPL Electric Utilities Corp [Member] | Power Purchase Agreement OVEC [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	0	0
PPL Electric Utilities Corp [Member] | Net deferred taxes [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	660	668
PPL Electric Utilities Corp [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	0	0
PPL Electric Utilities Corp [Member] | Terminated interest rate swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	0	0
PPL Electric Utilities Corp [Member] | TCJA bill credit [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	0	0
PPL Electric Utilities Corp [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	0	0
Noncurrent regulatory liabilities	2	0
LG And E And KU Energy LLC [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	63	9
Noncurrent regulatory liabilities	2,027	2,036
LG And E And KU Energy LLC [Member] | Environmental Cost Recovery [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	18	1
LG And E And KU Energy LLC [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	2	3
LG And E And KU Energy LLC [Member] | Gas Line Tracker [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	2	3
LG And E And KU Energy LLC [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	677	677
LG And E And KU Energy LLC [Member] | Power Purchase Agreement OVEC [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	66	68
LG And E And KU Energy LLC [Member] | Net deferred taxes [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	1,179	1,185
LG And E And KU Energy LLC [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	28	27
LG And E And KU Energy LLC [Member] | Terminated interest rate swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	74	74
LG And E And KU Energy LLC [Member] | TCJA bill credit [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	34	0
LG And E And KU Energy LLC [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	7	2
Noncurrent regulatory liabilities	3	5
Louisville Gas And Electric Co [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	29	3
Noncurrent regulatory liabilities	912	919
Louisville Gas And Electric Co [Member] | Environmental Cost Recovery [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	7	0
Louisville Gas And Electric Co [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	0	0
Louisville Gas And Electric Co [Member] | Gas Line Tracker [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	2	3
Louisville Gas And Electric Co [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	280	282
Louisville Gas And Electric Co [Member] | Power Purchase Agreement OVEC [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	46	47
Louisville Gas And Electric Co [Member] | Net deferred taxes [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	549	552
Louisville Gas And Electric Co [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	0	0
Louisville Gas And Electric Co [Member] | Terminated interest rate swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	37	37
Louisville Gas And Electric Co [Member] | TCJA bill credit [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	16	0
Louisville Gas And Electric Co [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	4	0
Noncurrent regulatory liabilities	0	1
Kentucky Utilities Co [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	34	6
Noncurrent regulatory liabilities	1,115	1,117
Kentucky Utilities Co [Member] | Environmental Cost Recovery [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	11	1
Kentucky Utilities Co [Member] | Fuel Adjustment Clause [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	2	3
Kentucky Utilities Co [Member] | Gas Line Tracker [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	0	0
Kentucky Utilities Co [Member] | Accumulated Cost Of Removal Of Utility Plant [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	397	395
Kentucky Utilities Co [Member] | Power Purchase Agreement OVEC [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	20	21
Kentucky Utilities Co [Member] | Net deferred taxes [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	630	633
Kentucky Utilities Co [Member] | Defined Benefit Plans [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	28	27
Kentucky Utilities Co [Member] | Terminated interest rate swaps [Member]
Regulatory Liabilities [Line Items]
Noncurrent regulatory liabilities	37	37
Kentucky Utilities Co [Member] | TCJA bill credit [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	18	0
Kentucky Utilities Co [Member] | Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Current regulatory liabilities	3	2
Noncurrent regulatory liabilities	$ 3	$ 4

Utility Rate Regulation - Reg52

Utility Rate Regulation - Regulatory Matters (Details) - USD ($) $ in Millions	Mar. 20, 2018	Jan. 29, 2018	Jan. 10, 2018	Aug. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
LKE [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase Decrease Amended Amount	$ 27
LGE [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Electric Service			$ 104
Advanced Metering Systems Deployment Incremental O&M Cost, Electric Service			11
LGE [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Gas Service			62
Advanced Metering Systems Deployment Incremental O&M Cost, Gas Service			3
LGE [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		$ 69
Approved Revenue Reduction Refunded Through Existing Mechanisms	20
Approved Revenue Reduction Refunded Through New Bill Credit	59
Public Utilities, Approved Rate Increase (Decrease), Amount	79
Proposed Revenue Reduction Refunded Through Existing Mechanisms		20
Proposed Revenue Reduction Refunded Through New Bill Credit		49
LGE [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Gas Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		17
KU [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Electric Service			155
Advanced Metering Systems Deployment Incremental O&M Cost, Electric Service			17
KU [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		91
Approved Revenue Reduction Refunded Through Existing Mechanisms	21
Approved Revenue Reduction Refunded Through New Bill Credit	87
Public Utilities, Approved Rate Increase (Decrease), Amount	108
Proposed Revenue Reduction Refunded Through Existing Mechanisms		21
Proposed Revenue Reduction Refunded Through New Bill Credit		70
LG And E And KU Energy LLC [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase Decrease Amended Amount	27
LG And E And KU Energy LLC [Member] | LGE [Member]
Regulatory Matters - Kentucky Activities - Gas Franchise (Numeric) [Abstract]
Franchise Agreement Term				5 years
Days of Notice to Modify Franchise Fee				60 days
Franchise Fee Cap				3.00%
Franchise Fee If Recovered From Customers				0.00%
LG And E And KU Energy LLC [Member] | LGE [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Electric Service			104
Advanced Metering Systems Deployment Incremental O&M Cost, Electric Service			11
LG And E And KU Energy LLC [Member] | LGE [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Gas Service			62
Advanced Metering Systems Deployment Incremental O&M Cost, Gas Service			3
LG And E And KU Energy LLC [Member] | LGE [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		69
Approved Revenue Reduction Refunded Through Existing Mechanisms	20
Approved Revenue Reduction Refunded Through New Bill Credit	59
Public Utilities, Approved Rate Increase (Decrease), Amount	79
Proposed Revenue Reduction Refunded Through Existing Mechanisms		20
Proposed Revenue Reduction Refunded Through New Bill Credit		49
LG And E And KU Energy LLC [Member] | LGE [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Gas Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		17
LG And E And KU Energy LLC [Member] | KU [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Electric Service			155
Advanced Metering Systems Deployment Incremental O&M Cost, Electric Service			17
LG And E And KU Energy LLC [Member] | KU [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		91
Approved Revenue Reduction Refunded Through Existing Mechanisms	21
Approved Revenue Reduction Refunded Through New Bill Credit	87
Public Utilities, Approved Rate Increase (Decrease), Amount	108
Proposed Revenue Reduction Refunded Through Existing Mechanisms		21
Proposed Revenue Reduction Refunded Through New Bill Credit		70
Louisville Gas And Electric Co [Member]
Regulatory Matters - Kentucky Activities - Gas Franchise (Numeric) [Abstract]
Franchise Agreement Term				5 years
Days of Notice to Modify Franchise Fee				60 days
Franchise Fee Cap				3.00%
Franchise Fee If Recovered From Customers				0.00%
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Electric Service			104
Advanced Metering Systems Deployment Incremental O&M Cost, Electric Service			11
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | Gas Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Gas Service			62
Advanced Metering Systems Deployment Incremental O&M Cost, Gas Service			3
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		69
Approved Revenue Reduction Refunded Through Existing Mechanisms	20
Approved Revenue Reduction Refunded Through New Bill Credit	59
Public Utilities, Approved Rate Increase (Decrease), Amount	79
Public Utilities, Proposed Rate Increase Decrease Amended Amount	10
Proposed Revenue Reduction Refunded Through Existing Mechanisms		20
Proposed Revenue Reduction Refunded Through New Bill Credit		49
Louisville Gas And Electric Co [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Gas Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		17
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Advanced Metering Systems Deployment Estimated Capital Cost, Electric Service			155
Advanced Metering Systems Deployment Incremental O&M Cost, Electric Service			$ 17
Kentucky Utilities Co [Member] | Kentucky Public Service Commission [Member] | TCJA Savings Distributed To Customers [Member] | Electric Rates [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Public Utilities, Proposed Rate Increase (Decrease), Amount		91
Approved Revenue Reduction Refunded Through Existing Mechanisms	21
Approved Revenue Reduction Refunded Through New Bill Credit	87
Public Utilities, Approved Rate Increase (Decrease), Amount	108
Public Utilities, Proposed Rate Increase Decrease Amended Amount	$ 17
Proposed Revenue Reduction Refunded Through Existing Mechanisms		21
Proposed Revenue Reduction Refunded Through New Bill Credit		$ 70
Unaffiliated Third Party Entity [Member] | PPL Electric [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Purchases of Accounts Receivable					$ 376	$ 356
Unaffiliated Third Party Entity [Member] | PPL Electric Utilities Corp [Member]
Regulatory Matters - Kentucky Activities - Rate Case Proceedings (Numeric) [Abstract]
Purchases of Accounts Receivable					$ 376	$ 356

Utility Rate Regulation Utility

Utility Rate Regulation Utility Rate Regulation (Other) (Detail (Details) - Unaffiliated Third Party Entity [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
PPL Electric [Member]
Purchases Of Accounts Receivable [Line Items]
Purchases of Accounts Receivable	$ 376	$ 356
PPL Electric Utilities Corp [Member]
Purchases Of Accounts Receivable [Line Items]
Purchases of Accounts Receivable	$ 376	$ 356

Financing Activities - Credit A

Financing Activities - Credit Arrangements (Details) £ in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2018GBP (£)	Jan. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2017GBP (£)
UNITED KINGDOM
Line of Credit Facility [Line Items]
Capacity | £		£ 1,315
Borrowed | £		497			£ 448
Letters of Credit and Commercial Paper Issued | £		4			4
Unused Capacity	$ 1,100	816
UNITED KINGDOM | Uncommitted Credit Facilities [Member]
Line of Credit Facility [Line Items]
Capacity | £		130
Borrowed | £		0			0
Letters of Credit and Commercial Paper Issued | £		4			4
Unused Capacity | £		126
WPD PLC [Member] | UNITED KINGDOM | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2022
Capacity | £		210
Borrowed	$ 200	145		$ 200	148
Letters of Credit and Commercial Paper Issued | £		0			£ 0
Unused Capacity | £		£ 67
Interest rate on outstanding borrowing	2.47%	2.47%		2.17%	2.17%
Borrowings | £		£ 143
WPD PLC [Member] | UNITED KINGDOM | Index Linked Term Loan [Member]
Line of Credit Facility [Line Items]
Expiration Date	Dec. 31, 2018
Capacity | £		130
Borrowed	$ 179	130
Letters of Credit and Commercial Paper Issued | £		0
Unused Capacity | £		£ 0
Interest rate on outstanding borrowing	1.77%	1.77%
WPD South West [Member] | UNITED KINGDOM | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jul. 31, 2021
Capacity | £		£ 245
Borrowed | £		0			£ 0
Letters of Credit and Commercial Paper Issued | £		0			0
Unused Capacity | £		245
WPD East Midlands [Member] | UNITED KINGDOM | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jul. 31, 2021
Capacity | £		300
Borrowed	$ 216	157		$ 244	180
Letters of Credit and Commercial Paper Issued | £		0			£ 0
Unused Capacity | £		£ 143
Interest rate on outstanding borrowing	0.90%	0.90%		0.89%	0.89%
WPD West Midlands [Member] | UNITED KINGDOM | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jul. 31, 2021
Capacity | £		£ 300
Borrowed	$ 89	65		$ 162	£ 120
Letters of Credit and Commercial Paper Issued | £		0			£ 0
Unused Capacity | £		£ 235
Interest rate on outstanding borrowing	0.90%	0.90%		0.89%	0.89%
PPL Capital Funding [Member] | UNITED STATES
Line of Credit Facility [Line Items]
Capacity	$ 1,350
Borrowed	0			$ 0
Letters of Credit and Commercial Paper Issued	369			248
Unused Capacity	$ 981
PPL Capital Funding [Member] | UNITED STATES | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 950
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	345			230
Unused Capacity	$ 605
PPL Capital Funding [Member] | UNITED STATES | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Nov. 30, 2018
Capacity	$ 300
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	0			0
Unused Capacity	$ 300
PPL Capital Funding [Member] | UNITED STATES | Bilateral Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Mar. 31, 2019
Capacity	$ 100
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	24			18
Unused Capacity	$ 76
PPL Electric [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 650
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	214			1
Unused Capacity	$ 436
LKE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Oct. 31, 2018
Capacity	$ 75
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	0			0
Unused Capacity	75
LGE [Member]
Line of Credit Facility [Line Items]
Capacity	700
Borrowed	200			100
Letters of Credit and Commercial Paper Issued	137			199
Unused Capacity	$ 363
LGE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 500
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	137			199
Unused Capacity	$ 363
LGE [Member] | Term Loan Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Oct. 31, 2019
Capacity	$ 200
Borrowed	200		$ 100	100
Letters of Credit and Commercial Paper Issued	0			0
Unused Capacity	0
KU [Member]
Line of Credit Facility [Line Items]
Capacity	598
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	276			243
Unused Capacity	$ 322
KU [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 400
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	78			45
Unused Capacity	$ 322
KU [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Oct. 31, 2020
Capacity	$ 198
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	198			198
Unused Capacity	$ 0
PPL Electric Utilities Corp [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 650
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	214			1
Unused Capacity	$ 436
LG And E And KU Energy LLC [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Oct. 31, 2018
Capacity	$ 75
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	0			0
Unused Capacity	75
LG And E And KU Energy LLC [Member] | LGE [Member]
Line of Credit Facility [Line Items]
Capacity	700
Borrowed	200			100
Letters of Credit and Commercial Paper Issued	137			199
Unused Capacity	$ 363
LG And E And KU Energy LLC [Member] | LGE [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 500
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	137			199
Unused Capacity	$ 363
LG And E And KU Energy LLC [Member] | LGE [Member] | Term Loan Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Oct. 31, 2019
Capacity	$ 200
Borrowed	200		100	100
Letters of Credit and Commercial Paper Issued	0			0
Unused Capacity	0
LG And E And KU Energy LLC [Member] | KU [Member]
Line of Credit Facility [Line Items]
Capacity	598
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	276			243
Unused Capacity	$ 322
LG And E And KU Energy LLC [Member] | KU [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 400
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	78			45
Unused Capacity	$ 322
LG And E And KU Energy LLC [Member] | KU [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Oct. 31, 2020
Capacity	$ 198
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	198			198
Unused Capacity	0
Louisville Gas And Electric Co [Member]
Line of Credit Facility [Line Items]
Capacity	700
Borrowed	200			100
Letters of Credit and Commercial Paper Issued	137			199
Unused Capacity	$ 363
Louisville Gas And Electric Co [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 500
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	137			199
Unused Capacity	$ 363
Louisville Gas And Electric Co [Member] | Term Loan Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Oct. 31, 2019
Capacity	$ 200
Borrowed	200		$ 100	100
Letters of Credit and Commercial Paper Issued	0			0
Unused Capacity	0
Kentucky Utilities Co [Member]
Line of Credit Facility [Line Items]
Capacity	598
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	276			243
Unused Capacity	$ 322
Kentucky Utilities Co [Member] | Syndicated Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Jan. 31, 2023
Capacity	$ 400
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	78			45
Unused Capacity	$ 322
Kentucky Utilities Co [Member] | Letter Of Credit Facility [Member]
Line of Credit Facility [Line Items]
Expiration Date	Oct. 31, 2020
Capacity	$ 198
Borrowed	0			0
Letters of Credit and Commercial Paper Issued	198			$ 198
Unused Capacity	$ 0

Financing Activities - Short-te

Financing Activities - Short-term Debt (Details) - Commercial Paper [Member] - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Short-term Debt [Line Items]
Capacity	$ 2,350
Commercial Paper Issuances	773	$ 474
Unused Capacity	$ 1,577
PPL Capital Funding [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.44%	1.64%
Capacity	$ 1,000
Commercial Paper Issuances	345	$ 230
Unused Capacity	$ 655
PPL Electric [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.42%
Capacity	$ 650
Commercial Paper Issuances	213	$ 0
Unused Capacity	$ 437
LGE [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.23%	1.83%
Capacity	$ 350
Commercial Paper Issuances	137	$ 199
Unused Capacity	$ 213
KU [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.35%	1.97%
Capacity	$ 350
Commercial Paper Issuances	78	$ 45
Unused Capacity	$ 272
PPL Electric Utilities Corp [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.42%
Capacity	$ 650
Commercial Paper Issuances	213	$ 0
Unused Capacity	$ 437
LG And E And KU Energy LLC [Member] | LGE [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.23%	1.83%
Capacity	$ 350
Commercial Paper Issuances	137	$ 199
Unused Capacity	$ 213
LG And E And KU Energy LLC [Member] | KU [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.35%	1.97%
Capacity	$ 350
Commercial Paper Issuances	78	$ 45
Unused Capacity	$ 272
Louisville Gas And Electric Co [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.23%	1.83%
Capacity	$ 350
Commercial Paper Issuances	137	$ 199
Unused Capacity	$ 213
Kentucky Utilities Co [Member]
Short-term Debt [Line Items]
Weighted - Average Interest Rate	2.35%	1.97%
Capacity	$ 350
Commercial Paper Issuances	78	$ 45
Unused Capacity	$ 272

Financing Activities - Long-ter

Financing Activities - Long-term Debt and ATM Program (Details) shares in Thousands, £ in Millions, $ in Millions	1 Months Ended			3 Months Ended
	May 31, 2018USD ($)	Mar. 31, 2018USD ($)	Mar. 31, 2018GBP (£)	Mar. 31, 2018USD ($)shares	Mar. 31, 2017USD ($)	Mar. 31, 2018GBP (£)	Feb. 28, 2018USD ($)
At-the-Market Stock Offering Program (Numeric) [Abstract]
Net proceeds from issuance of common stock				$ 100	$ 73
WPD South Wales PLC [Member] | Index Linked Senior Unsecured Notes [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount | £						£ 30
Stated interest rate		0.01%		0.01%		0.01%
Proceeds from debt, net of issuance costs | £			£ 31
Maturity date		Dec. 31, 2036	Dec. 31, 2036
Proceeds from debt, including premium net of debt issuance costs		$ 44
LGE [Member] | Senior Debt Obligations [Member] | Pollution Control Revenue Bonds, 2001 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount		$ 28		$ 28
Stated interest rate		2.30%		2.30%		2.30%
Maturity date		Dec. 31, 2026	Dec. 31, 2026
Repurchase date of debt instruments		Sep. 1, 2021	Sep. 1, 2021
LGE [Member] | Senior Debt Obligations [Member] | Pollution Control Revenue Bonds, 2001 Series B [Member] | Remarketed [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 35
Stated interest rate	2.55%
Maturity date	Dec. 31, 2027
Repurchase date of debt instruments	May 3, 2021
LGE [Member] | Senior Debt Obligations [Member] | Jefferson County Pollution Control Revenue Bonds, 2001 Series B [Member] | Remarketed [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 35
Stated interest rate	2.55%
Maturity date	Dec. 31, 2027
Repurchase date of debt instruments	May 3, 2021
LG And E And KU Energy LLC [Member] | LGE [Member] | Senior Debt Obligations [Member] | Pollution Control Revenue Bonds, 2001 Series A [Member] | Remarketed [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount		$ 28		$ 28
Stated interest rate		2.30%		2.30%		2.30%
Maturity date		Dec. 31, 2026	Dec. 31, 2026
Repurchase date of debt instruments		Sep. 1, 2021	Sep. 1, 2021
LG And E And KU Energy LLC [Member] | LGE [Member] | Senior Debt Obligations [Member] | Pollution Control Revenue Bonds, 2001 Series B [Member] | Remarketed [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 35
Stated interest rate	2.55%
Maturity date	Dec. 31, 2027
Repurchase date of debt instruments	May 3, 2021
LG And E And KU Energy LLC [Member] | LGE [Member] | Senior Debt Obligations [Member] | Jefferson County Pollution Control Revenue Bonds, 2001 Series B [Member] | Remarketed [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 35
Stated interest rate	2.55%
Maturity date	Dec. 31, 2027
Repurchase date of debt instruments	May 3, 2021
LG And E And KU Energy LLC [Member] | Affiliated Entity [Member] | Note Payable [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Stated interest rate	4.00%
Maturity date	May 31, 2028
Notes Payable, Noncurrent	$ 250
Louisville Gas And Electric Co [Member] | Senior Debt Obligations [Member] | Pollution Control Revenue Bonds, 2001 Series A [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount		$ 28		$ 28
Stated interest rate		2.30%		2.30%		2.30%
Maturity date		Dec. 31, 2026	Dec. 31, 2026
Repurchase date of debt instruments		Sep. 1, 2021	Sep. 1, 2021
Louisville Gas And Electric Co [Member] | Senior Debt Obligations [Member] | Pollution Control Revenue Bonds, 2001 Series B [Member] | Remarketed [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 35
Stated interest rate	2.55%
Maturity date	Dec. 31, 2027
Repurchase date of debt instruments	May 3, 2021
Louisville Gas And Electric Co [Member] | Senior Debt Obligations [Member] | Jefferson County Pollution Control Revenue Bonds, 2001 Series B [Member] | Remarketed [Member] | Subsequent Event [Member]
Long-term Debt (Numeric) [Abstract]
Principal amount	$ 35
Stated interest rate	2.55%
Maturity date	Dec. 31, 2027
Repurchase date of debt instruments	May 3, 2021
At The Market Stock Offering Program [Member]
At-the-Market Stock Offering Program (Numeric) [Abstract]
Aggregate sales price of common stock based on two separate equity distribution agreements							$ 1,000
Stock Issued During Period, Shares, New Issues | shares				3,000
Net proceeds from issuance of common stock				$ 85

Financing Activities - Distribu

Financing Activities - Distributions (Details) - $ / shares	1 Months Ended	3 Months Ended
	Feb. 28, 2018	Mar. 31, 2018	Mar. 31, 2017
Distributions (Numeric) [Abstract]
Dividend payable date of quarterly common stock dividend	Apr. 2, 2018
Current quarterly common stock dividend (in dollars per share)	$ 0.410	$ 0.41	$ 0.395
Annualized current quarterly common stock dividend (in dollars per share)	$ 1.64

Defined Benefits (Details)

Defined Benefits (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Pension Plan [Member] | U.S.
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	$ 16	$ 17
Interest cost	39	42
Expected return on plan assets	(62)	(57)
Amortization of: [Abstract]
Prior service cost	2	2
Actuarial loss	22	20
Net periodic defined benefit costs (credits) before settlements and special termination benefits	17	24
Special termination benefits	0	2
Net periodic defined benefit costs (credits)	17	26
Pension Plan [Member] | U.K.
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	21	19
Interest cost	47	43
Expected return on plan assets	(150)	(125)
Amortization of: [Abstract]
Prior service cost	0	0
Actuarial loss	39	35
Net periodic defined benefit costs (credits) before settlements and special termination benefits	(43)	(28)
Special termination benefits	0	0
Net periodic defined benefit costs (credits)	(43)	(28)
Other Postretirement Benefits Plan [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	1	2
Interest cost	3	6
Expected return on plan assets	(4)	(6)
Amortization of: [Abstract]
Prior service cost	(1)	0
Net periodic defined benefit costs (credits)	(1)	2
PPL Electric Utilities Corp [Member] | PPL Services [Member]
Net Periodic Defined Benefit Costs Allocated to Subsidiary by Sponsor (Numeric) [Abstract]
Costs allocated to subsidiary by plan sponsors	4	8
LG And E And KU Energy LLC [Member] | Pension Plan [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	7	7
Interest cost	16	16
Expected return on plan assets	(26)	(22)
Amortization of: [Abstract]
Prior service cost	2	2
Actuarial loss	$ 10	$ 11
Regulatory Asset Amortization Period	15 years	15 years
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period	$ 4	$ 5
Net periodic defined benefit costs (credits)	9	14
LG And E And KU Energy LLC [Member] | Other Postretirement Benefits Plan [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Service cost	1	1
Interest cost	2	2
Expected return on plan assets	(2)	(1)
Amortization of: [Abstract]
Net periodic defined benefit costs (credits)	1	2
Louisville Gas And Electric Co [Member] | LKE [Member]
Net Periodic Defined Benefit Costs Allocated to Subsidiary by Sponsor (Numeric) [Abstract]
Costs allocated to subsidiary by plan sponsors	2	3
Louisville Gas And Electric Co [Member] | Pension Plan [Member]
Net Periodic Defined Benefit Costs (Credits) (Details) [Abstract]
Interest cost	3	3
Expected return on plan assets	(5)	(5)
Amortization of: [Abstract]
Prior service cost	1	1
Actuarial loss	$ 2	$ 3
Regulatory Asset Amortization Period	15 years	15 years
Deferred recovery of the difference between pension costs calculated with pension accounting policy and pension cost using 15 year amortization period	$ 1	$ 1
Net periodic defined benefit costs (credits)	1	2
Kentucky Utilities Co [Member] | LKE [Member]
Net Periodic Defined Benefit Costs Allocated to Subsidiary by Sponsor (Numeric) [Abstract]
Costs allocated to subsidiary by plan sponsors	$ 1	$ 4

Commitments and Contingencies -

Commitments and Contingencies - Legal Matters and Regulatory Issues (Details)	3 Months Ended
	Mar. 31, 2018claimresidentcoal-fired_unitmi
LGE [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of residents that filed class action suit | resident	6
Number of miles within plant that would include a class of residents	4
Number of remaining unresolved Clean Air Act violation claims after July 2014 court ruling | claim	1
Generating units retired at the Cane Run plant | coal-fired_unit	3
LGE [Member] | Minimum [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of miles within plant that would include a class of residents	1
LGE [Member] | Maximum [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of miles within plant that would include a class of residents	3
LG And E And KU Energy LLC [Member] | LGE [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of residents that filed class action suit | resident	6
Number of miles within plant that would include a class of residents	4
Number of remaining unresolved Clean Air Act violation claims after July 2014 court ruling | claim	1
Generating units retired at the Cane Run plant | coal-fired_unit	3
LG And E And KU Energy LLC [Member] | LGE [Member] | Minimum [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of miles within plant that would include a class of residents	1
LG And E And KU Energy LLC [Member] | LGE [Member] | Maximum [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of miles within plant that would include a class of residents	3
Louisville Gas And Electric Co [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of residents that filed class action suit | resident	6
Number of miles within plant that would include a class of residents	4
Number of remaining unresolved Clean Air Act violation claims after July 2014 court ruling | claim	1
Generating units retired at the Cane Run plant | coal-fired_unit	3
Louisville Gas And Electric Co [Member] | Minimum [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of miles within plant that would include a class of residents	1
Louisville Gas And Electric Co [Member] | Maximum [Member]
Legal Matters - Cane Run Environmental Claims (Numeric) [Abstract]
Number of miles within plant that would include a class of residents	3

Commitments and Contingencies60

Commitments and Contingencies - Environmental Matters and Other (Details) - PPL Electric Additional Sites [Member] - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
PPL Electric [Member]
Environmental Matters - Superfund and Other Remediation (Numeric) [Abstract]
Environmental site accrual	$ 11	$ 10
PPL Electric Utilities Corp [Member]
Environmental Matters - Superfund and Other Remediation (Numeric) [Abstract]
Environmental site accrual	$ 11	$ 10

Commitments and Contingencies61

Commitments and Contingencies - Guarantees and Other Assurances (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)Integer	Dec. 31, 2017USD ($)
Guarantor Obligations [Line Items]
Recorded liability for all guarantees	$ 7	$ 17
Other Guarantee (Numeric) [Abstract]
Maximum aggregate coverage bodily injury and property damage	$ 225
PPL Guarantee [Member] | Indemnification Guarantee [Member] | Indemnifications Related To WPD Midlands Acquisition [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimable	The maximum exposure and expiration of these indemnifications cannot be estimated because the maximum potential liability is not capped and the expiration date is not specified in the transaction documents.
PPL Guarantee [Member] | Indemnification Guarantee [Member] | WPD Indemnifications For Entities In Liquidation and Sales Of Assets [Member]
Guarantor Obligations [Line Items]
Maximum exposure	$ 11
Expiration date	2,020
Minimum Period In Years That Indemnifications Generally Expire | Integer	2
Maximum Period In Years That Indemnifications Generally Expire | Integer	7
PPL Guarantee [Member] | Financial Guarantee [Member] | WPD Guarantee Of Pension And Other Obligations Of Unconsolidated Entities [Member]
Guarantor Obligations [Line Items]
Maximum exposure	$ 99
PPL Electric Guarantee [Member] | Indemnification Guarantee [Member] | Guarantee Of Inventory Value [Member]
Guarantor Obligations [Line Items]
Maximum exposure	$ 17
Expiration date	2,020
LKE Guarantee [Member] | Indemnification Guarantee [Member] | Indemnification Of Lease Termination And Other Divestitures [Member]
Guarantor Obligations [Line Items]
Maximum exposure	$ 201
Expiration date	2,021
Term of guarantee (in years)	12
Maximum exposure of guarantee related to terminated lease specific to operational, regulatory and environmental issues	$ 200
LKE Guarantee [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimable	The maximum exposure and the expiration date of these potential obligations are not presently determinable.
Contingent proportionate share of OVEC's outstanding debt	$ 117
PPL Electric Utilities Corp [Member] | Indemnification Guarantee [Member] | Guarantee Of Inventory Value [Member]
Guarantor Obligations [Line Items]
Maximum exposure	$ 17
Expiration date	2,020
LG And E And KU Energy LLC [Member]
Guarantor Obligations [Line Items]
Recorded liability for all guarantees		$ 11
LG And E And KU Energy LLC [Member] | Indemnification Guarantee [Member] | Indemnification Of Lease Termination And Other Divestitures [Member]
Guarantor Obligations [Line Items]
Maximum exposure	$ 201
Expiration date	2,021
Term of guarantee (in years)	12
Maximum exposure of guarantee related to terminated lease specific to operational, regulatory and environmental issues	$ 200
LG And E And KU Energy LLC [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimable	The maximum exposure and the expiration date of these potential obligations are not presently determinable.
Contingent proportionate share of OVEC's outstanding debt	$ 117
Louisville Gas And Electric Co [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimable	The maximum exposure and the expiration date of these potential obligations are not presently determinable.
Louisville Gas And Electric Co [Member] | LGE And KU Guarantee [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Contingent proportionate share of OVEC's outstanding debt	$ 81
Kentucky Utilities Co [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Maximum exposure is not estimable	The maximum exposure and the expiration date of these potential obligations are not presently determinable.
Kentucky Utilities Co [Member] | LGE And KU Guarantee [Member] | Financial Guarantee [Member] | LGE And KU Guarantee Of Shortfall Related To OVEC [Member]
Guarantor Obligations [Line Items]
Contingent proportionate share of OVEC's outstanding debt	$ 36

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	May 31, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Feb. 28, 2018
PPL Electric Utilities Corp [Member] | PPL Services [Member]
Support Costs (Details) [Abstract]
Support cost allocations from subsidiary of parent to registrant		$ 16	$ 51
PPL Electric Utilities Corp [Member] | PPL EU Services [Member]
Support Costs (Details) [Abstract]
Support cost allocations from subsidiary of parent to registrant		35	18
PPL Electric Utilities Corp [Member] | PPL Energy Funding [Member]
Intercompany Borrowings (Numeric) [Abstract]
Intercompany note with affiliate maximum borrowing capacity		400
Notes receivable from affiliate		0		$ 0
LG And E And KU Energy LLC [Member]
Intercompany Borrowings (Numeric) [Abstract]
Notes payable to affiliates		237		225
Long-term debt to affiliate		400		400
Interest Expense with Affiliate		5	4
LG And E And KU Energy LLC [Member] | PPL Services [Member]
Support Costs (Details) [Abstract]
Support cost allocations from subsidiary of parent to registrant		7	6
LG And E And KU Energy LLC [Member] | PPL Energy Funding [Member]
Intercompany Borrowings (Numeric) [Abstract]
Intercompany note with affiliate maximum borrowing capacity		300
Notes payable to affiliates		$ 237		$ 225
Intercompany borrowings demand note rate on outstanding borrowing		3.17%		2.87%
Intercompany Note Affiliate Maximum Borrowing Capacity Increase					$ 25
LG And E And KU Energy LLC [Member] | PPL Affiliate [Member]
Intercompany Borrowings (Numeric) [Abstract]
Debt instrument term (in years)		10 years
Long-term debt to affiliate		$ 400
Interest rate on ten-year note		3.50%
Interest Expense with Affiliate		$ 4	4
LG And E And KU Energy LLC [Member] | Note Payable [Member] | Affiliated Entity [Member] | Subsequent Event [Member]
Intercompany Borrowings (Numeric) [Abstract]
Stated interest rate	4.00%
Maturity date	May 31, 2028
Notes Payable, Noncurrent	$ 250
Louisville Gas And Electric Co [Member] | LKS [Member]
Intercompany Billings by LKS (Details) [Abstract]
Intercompany billings between affiliates		38	44
Kentucky Utilities Co [Member] | LKS [Member]
Intercompany Billings by LKS (Details) [Abstract]
Intercompany billings between affiliates		$ 42	$ 44

Other Income (Expense)- net O63

Other Income (Expense)- net Other Income (Expense) - net (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Other Expense
Economic foreign currency exchange contracts	$ 112	$ 43
Charitable Contributions	4	4
Miscellaneous	1	11
Total Other Expense	117	58
Other Income [Line Items]
Defined benefit plans - non-service credits	68	38
Allowance for Funds Used During Construction - equity component	5	2
Miscellaneous	1	9
Total Other Income	74	49
Other Income (Expense) - net	(43)	(9)
PPL Electric Utilities Corp [Member]
Other Expense
Charitable Contributions	1	1
Defined benefit plans - non-service costs	0	1
Total Other Expense	1	2
Other Income [Line Items]
Defined benefit plans - non-service credits	2	0
Allowance for Funds Used During Construction - equity component	5	2
Total Other Income	7	2
Other Income (Expense) - net	$ 6	$ 0

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured on Recurring Basis Table (Details) - Recurring Fair Value Measurements [Member] - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Assets
Cash and cash equivalents	$ 629	$ 485
Restricted cash and cash equivalents	24	26
Price risk management assets:
Foreign currency contracts	97	163
Cross-currency swaps	79	101
Total price risk management assets	176	264
Total assets	829	775
Price risk management liabilities:
Interest rate swaps	22	26
Foreign currency contracts	167	148
Total price risk management liabilities	189	174
Level 1 [Member]
Assets
Cash and cash equivalents	629	485
Restricted cash and cash equivalents	24	26
Price risk management assets:
Foreign currency contracts	0	0
Cross-currency swaps	0	0
Total price risk management assets	0	0
Total assets	653	511
Price risk management liabilities:
Interest rate swaps	0	0
Foreign currency contracts	0	0
Total price risk management liabilities	0	0
Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Restricted cash and cash equivalents	0	0
Price risk management assets:
Foreign currency contracts	97	163
Cross-currency swaps	79	101
Total price risk management assets	176	264
Total assets	176	264
Price risk management liabilities:
Interest rate swaps	22	26
Foreign currency contracts	167	148
Total price risk management liabilities	189	174
Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Restricted cash and cash equivalents	0	0
Price risk management assets:
Foreign currency contracts	0	0
Cross-currency swaps	0	0
Total price risk management assets	0	0
Total assets	0	0
Price risk management liabilities:
Interest rate swaps	0	0
Foreign currency contracts	0	0
Total price risk management liabilities	0	0
PPL Electric Utilities Corp [Member]
Assets
Cash and cash equivalents	20	49
Restricted cash and cash equivalents	2	2
Price risk management assets:
Total assets	22	51
PPL Electric Utilities Corp [Member] | Level 1 [Member]
Assets
Cash and cash equivalents	20	49
Restricted cash and cash equivalents	2	2
Price risk management assets:
Total assets	22	51
PPL Electric Utilities Corp [Member] | Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Restricted cash and cash equivalents	0	0
Price risk management assets:
Total assets	0	0
PPL Electric Utilities Corp [Member] | Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Restricted cash and cash equivalents	0	0
Price risk management assets:
Total assets	0	0
LG And E And KU Energy LLC [Member]
Assets
Cash and cash equivalents	27	30
Price risk management assets:
Total assets	27	30
Price risk management liabilities:
Interest rate swaps	22	26
Total price risk management liabilities	22	26
LG And E And KU Energy LLC [Member] | Level 1 [Member]
Assets
Cash and cash equivalents	27	30
Price risk management assets:
Total assets	27	30
Price risk management liabilities:
Interest rate swaps	0	0
Total price risk management liabilities	0	0
LG And E And KU Energy LLC [Member] | Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total assets	0	0
Price risk management liabilities:
Interest rate swaps	22	26
Total price risk management liabilities	22	26
LG And E And KU Energy LLC [Member] | Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total assets	0	0
Price risk management liabilities:
Interest rate swaps	0	0
Total price risk management liabilities	0	0
Louisville Gas And Electric Co [Member]
Assets
Cash and cash equivalents	14	15
Price risk management assets:
Total assets	14	15
Price risk management liabilities:
Interest rate swaps	22	26
Total price risk management liabilities	22	26
Louisville Gas And Electric Co [Member] | Level 1 [Member]
Assets
Cash and cash equivalents	14	15
Price risk management assets:
Total assets	14	15
Price risk management liabilities:
Interest rate swaps	0	0
Total price risk management liabilities	0	0
Louisville Gas And Electric Co [Member] | Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total assets	0	0
Price risk management liabilities:
Interest rate swaps	22	26
Total price risk management liabilities	22	26
Louisville Gas And Electric Co [Member] | Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total assets	0	0
Price risk management liabilities:
Interest rate swaps	0	0
Total price risk management liabilities	0	0
Kentucky Utilities Co [Member]
Assets
Cash and cash equivalents	11	15
Price risk management assets:
Total assets	11	15
Kentucky Utilities Co [Member] | Level 1 [Member]
Assets
Cash and cash equivalents	11	15
Price risk management assets:
Total assets	11	15
Kentucky Utilities Co [Member] | Level 2 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total assets	0	0
Kentucky Utilities Co [Member] | Level 3 [Member]
Assets
Cash and cash equivalents	0	0
Price risk management assets:
Total assets	$ 0	$ 0

Fair Value Measurements - Finan

Fair Value Measurements - Financial Instruments Not Recorded at Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Carrying Amount [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	$ 20,464	$ 20,195
Fair Value [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	23,577	23,783
PPL Electric Utilities Corp [Member] | Carrying Amount [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	3,298	3,298
PPL Electric Utilities Corp [Member] | Fair Value [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	3,632	3,769
LG And E And KU Energy LLC [Member] | Carrying Amount [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	5,259	5,159
LG And E And KU Energy LLC [Member] | Fair Value [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	5,654	5,670
Louisville Gas And Electric Co [Member] | Carrying Amount [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	1,808	1,709
Louisville Gas And Electric Co [Member] | Fair Value [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	1,925	1,865
Kentucky Utilities Co [Member] | Carrying Amount [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	2,329	2,328
Kentucky Utilities Co [Member] | Fair Value [Member]
Fair Value of Financial Instruments Not Recorded at Fair Value - Other
Long-term debt	$ 2,546	$ 2,605

Derivative Instruments and He66

Derivative Instruments and Hedging Activities - Intro (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Master Netting Arrangements (Numeric) [Line Items]
Cash Collateral Obligation Under Master Netting Arrangement	$ 16	$ 20
Cash collateral posted under master netting arrangements	5	0
LG And E And KU Energy LLC [Member]
Master Netting Arrangements (Numeric) [Line Items]
Cash Collateral Obligation Under Master Netting Arrangement	0	0
Cash collateral posted under master netting arrangements	0	0
Louisville Gas And Electric Co [Member]
Master Netting Arrangements (Numeric) [Line Items]
Cash Collateral Obligation Under Master Netting Arrangement	0	0
Cash collateral posted under master netting arrangements	0	0
Kentucky Utilities Co [Member]
Master Netting Arrangements (Numeric) [Line Items]
Cash Collateral Obligation Under Master Netting Arrangement	0	0
Cash collateral posted under master netting arrangements	$ 0	$ 0

Derivative Instruments and He67

Derivative Instruments and Hedging Activities - Risk Disclosures (Details) £ in Millions, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)	Mar. 31, 2018GBP (£)
Cash Flow Hedges [Member] | Cross Currency Interest Rate Swap Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount	$ 702
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
Earliest maturity date of cross-currency cash flow hedge contracts	2,021
Latest maturity date of cross-currency cash flow hedge contracts	2,028
Gain (Loss) on Interest Rate Cash Flow Hedge Ineffectiveness	$ 0	$ 0
Cash Flow Hedges [Member] | Interest Rate Swap Contracts [Member]
Interest Rate Risk - Cash Flow Hedges (Numeric) [Abstract]
No or insignificant after-tax gains (losses) previously recorded in AOCI reclassified to earnings related to interest rate cash flow hedge contracts	For the three months ended March 31, 2018, PPL had no cash flow hedges reclassified into earnings associated with discontinued cash flow hedges. For the three months ended March 31, 2017, PPL had an insignificant amount of cash flow hedges reclassified into earnings associated with discontinued cash flow hedges.
No or insignificant unrealized after-tax gains (losses) on interest rate cash flow hedge contracts expected to be reclassified into earnings during next 12 months	insignificant
Gain (Loss) on Interest Rate Cash Flow Hedge Ineffectiveness	$ 0	$ 0
Net Investment Hedges [Member] | Combined Foreign Currency Contracts And Intercompany Loans [Member]
Foreign Currency Risk - Net Investment Hedges (Numeric) [Abstract]
Net after tax gains (losses) on net investment hedges recognized in the foreign currency translation adjustment component of AOCI	20		$ 22
Net Investment Hedges [Member] | Foreign Currency Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount	$ 195			£ 140
Maximum Termination Date Net Investment Hedges Classified As Economic Activity	Jun. 30, 2018
Economic Hedges [Member] | Foreign Currency Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Maximum Termination Date Net Investment Hedges Classified As Economic Activity	Aug. 31, 2020
Foreign Currency Risk - Economic Activity (Numeric) [Abstract]
Total exposure hedged related to foreign currency contracts for anticipated earnings hedges classified as economic activity	$ 2,900			£ 2,100
Minimum Termination Date Net Investment Hedges Classified As Economic Activity	Apr. 30, 2018
Louisville Gas And Electric Co [Member] | Economic Hedges [Member] | Interest Rate Swap Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount	$ 147
Interest Rate Risk - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate economic activity contracts	2,033
LGE [Member] | Economic Hedges [Member] | Interest Rate Swap Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount	$ 147
Interest Rate Risk - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate economic activity contracts	2,033
LGE [Member] | LG And E And KU Energy LLC [Member] | Economic Hedges [Member] | Interest Rate Swap Contracts [Member]
Interest Rate Risk And Foreign Currency Risk [Line Items]
Notional amount	$ 147
Interest Rate Risk - Economic Activity (Numeric) [Abstract]
Year of expiration of the maximum maturity date of interest rate economic activity contracts	2,033

Derivative Instruments and He68

Derivative Instruments and Hedging Activities - Fair Values (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	$ 80	$ 101
Liability value	2	0
Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	5	4
Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Designated As Hedging Instruments [Member] | Current Assets [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	4	4
Designated As Hedging Instruments [Member] | Current Assets [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	1	0
Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	75	97
Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	75	97
Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	2	0
Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	0	0
Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	0	0
Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	2	0
Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	0	0
Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	0	0
Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	0	0
Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	0	0
Not Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	96	163
Liability value	187	174
Not Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	51	45
Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	51	45
Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	45	118
Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	45	118
Not Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	79	71
Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	4
Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	0	0
Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	75	67
Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	108	103
Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	18	22
Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Cross Currency Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	0	0
Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Foreign Currency Contracts [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	90	81
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Liability value	22	26
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	4
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	4
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	18	22
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	18	22
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Liability value	22	26
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Current Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Current Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Noncurrent Assets [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Asset value	0	0
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Current Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	4
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Current Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	4	4
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	18	22
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Noncurrent Liabilities [Member] | Interest Rate Swaps [Member]
Fair Values by Balance Sheet Location [Abstract]
Liability value	$ 18	$ 22

Derivative Instruments and He69

Derivative Instruments and Hedging Activities - Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash Flow Hedges [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	$ (14)	$ 2
Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	(1)
Cash Flow Hedges [Member] | Other Comprehensive Income (Loss) [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Derivative Gain (Loss) Recognized in OCI (Effective Portion)	(24)	(8)
Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Other Comprehensive Income (Loss) [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Derivative Gain (Loss) Recognized in OCI (Effective Portion)	0	0
Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(2)	(2)
Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	(1)
Cash Flow Hedges [Member] | Cross Currency Swaps [Member] | Other Comprehensive Income (Loss) [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Derivative Gain (Loss) Recognized in OCI (Effective Portion)	(24)	(8)
Cash Flow Hedges [Member] | Cross Currency Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)		1
Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)		0
Cash Flow Hedges [Member] | Cross Currency Swaps [Member] | Other Income (Expense) Net [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(12)	3
Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0
Net Investment Hedges [Member] | Foreign Currency Contracts [Member] | Other Comprehensive Income (Loss) [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Derivative Gain (Loss) Recognized in OCI (Effective Portion)	(1)	0
Not Designated As Hedging Instruments [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(113)	(45)
Not Designated As Hedging Instruments [Member] | Foreign Currency Contracts [Member] | Other Income (Expense) Net [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(112)	(43)
Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Regulatory Assets Noncurrent [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized as regulatory liabilities/assets	4	2
Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(1)	(2)
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Regulatory Assets Noncurrent [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized as regulatory liabilities/assets	4	2
LG And E And KU Energy LLC [Member] | Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	(1)	(2)
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Regulatory Assets Noncurrent [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized as regulatory liabilities/assets	4	2
Louisville Gas And Electric Co [Member] | Not Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]
Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]
Gain (loss) recognized in income on derivative	$ (1)	$ (2)

Derivative Instruments and He70

Derivative Instruments and Hedging Activities - Offsetting Derivative Instruments and Credit Risk-Related Features (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Credit Risk-Related Contingent Features [Abstract]
Aggregate fair value of derivative instruments in a net liability position with credit risk-related contingent features	$ 101
Aggregate fair value of collateral posted on these derivative instruments	10
Aggregate fair value of additional collateral requirements in the event of a credit downgrade below investment grade	91
Treasury Derivatives [Member]
Assets [Abstract]
Gross	176	$ 264
Derivative instruments - eligible for offset	78	107
Cash collateral received - eligible for offset	16	20
Net	82	137
Liabilities [Abstract]
Gross	189	174
Derivative instruments - eligible for offset	78	107
Cash collateral pledged - eligible for offset	5	0
Net	106	67
LG And E And KU Energy LLC [Member]
Credit Risk-Related Contingent Features [Abstract]
Aggregate fair value of derivative instruments in a net liability position with credit risk-related contingent features	8
Aggregate fair value of collateral posted on these derivative instruments	0
Aggregate fair value of additional collateral requirements in the event of a credit downgrade below investment grade	8
LG And E And KU Energy LLC [Member] | Treasury Derivatives [Member]
Assets [Abstract]
Gross	0	0
Derivative instruments - eligible for offset	0	0
Cash collateral received - eligible for offset	0	0
Net	0	0
Liabilities [Abstract]
Gross	22	26
Derivative instruments - eligible for offset	0	0
Cash collateral pledged - eligible for offset	0	0
Net	22	26
Louisville Gas And Electric Co [Member]
Credit Risk-Related Contingent Features [Abstract]
Aggregate fair value of derivative instruments in a net liability position with credit risk-related contingent features	8
Aggregate fair value of collateral posted on these derivative instruments	0
Aggregate fair value of additional collateral requirements in the event of a credit downgrade below investment grade	8
Louisville Gas And Electric Co [Member] | Treasury Derivatives [Member]
Assets [Abstract]
Gross	0	0
Derivative instruments - eligible for offset	0	0
Cash collateral received - eligible for offset	0	0
Net	0	0
Liabilities [Abstract]
Gross	22	26
Derivative instruments - eligible for offset	0	0
Cash collateral pledged - eligible for offset	0	0
Net	$ 22	$ 26

Asset Retirement Obligations (D

Asset Retirement Obligations (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	$ 397
Accretion	3
Effect of foreign exchange rates	1
Changes in estimated timing or cost	(10)
Obligations settled	(9)
Balance at End of Period	382
LG And E And KU Energy LLC [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	356
Accretion	3
Effect of foreign exchange rates	0
Changes in estimated timing or cost	(10)
Obligations settled	(9)
Balance at End of Period	340
Louisville Gas And Electric Co [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	121
Accretion	0
Effect of foreign exchange rates	0
Changes in estimated timing or cost	(5)
Obligations settled	(5)
Balance at End of Period	111
Kentucky Utilities Co [Member]
Asset Retirement Obligation [Roll Forward]
Balance at Beginning of Period	235
Accretion	3
Effect of foreign exchange rates	0
Changes in estimated timing or cost	(5)
Obligations settled	(4)
Balance at End of Period	$ 229

Accumulated Other Comprehensi72

Accumulated Other Comprehensive Income (Loss) - After-tax Changes by Component (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (3,422)	$ (3,778)
Amounts arising during the period	95	(30)
Reclassifications from accumulated other comprehensive income	48	31
Net other comprehensive income during the period	143	1
Balance at end of period	(3,279)	(3,777)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(1,089)	(1,627)
Amounts arising during the period	116	(24)
Reclassifications from accumulated other comprehensive income	0	0
Net other comprehensive income during the period	116	(24)
Balance at end of period	(973)	(1,651)
Qualifying Derivatives Unrealized Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(13)	(7)
Amounts arising during the period	(20)	(6)
Reclassifications from accumulated other comprehensive income	12	(1)
Net other comprehensive income during the period	(8)	(7)
Balance at end of period	(21)	(14)
Equity Investees Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	0	(1)
Amounts arising during the period	0	0
Reclassifications from accumulated other comprehensive income	0	0
Net other comprehensive income during the period	0	0
Balance at end of period	0	(1)
Defined Benefit Plans Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(7)	(8)
Amounts arising during the period	0	0
Reclassifications from accumulated other comprehensive income	0	0
Net other comprehensive income during the period	0	0
Balance at end of period	(7)	(8)
Defined Benefit Plans Actuarial Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(2,313)	(2,135)
Amounts arising during the period	(1)	0
Reclassifications from accumulated other comprehensive income	36	32
Net other comprehensive income during the period	35	32
Balance at end of period	$ (2,278)	$ (2,103)

Accumulated Other Comprehensi73

Accumulated Other Comprehensive Income (Loss) - Income (Expense) Effect of Reclassifications (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Affected Line Item on the Statements of Income [Line Items]
Other Income (Expense) - net	$ (43)	$ (9)
Interest Expense	(239)	(217)
Income Taxes	(117)	(129)
Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Total After-tax	(48)	(31)
Qualifying Derivatives [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Total Pre-tax	(14)	1
Income Taxes	2	0
Total After-tax	(12)	1
Qualifying Derivatives [Member] | Interest Rate Swaps [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Interest Expense	(2)	(3)
Qualifying Derivatives [Member] | Cross Currency Swaps [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Other Income (Expense) - net	(12)	3
Interest Expense	0	1
Defined Benefit Plans [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Total Pre-tax	(45)	(41)
Income Taxes	9	9
Total After-tax	(36)	(32)
Defined Benefit Plans [Member] | Net Actuarial Loss [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income [Line Items]
Total Pre-tax	$ (45)	$ (41)

New Accounting Guidance Pendi74

New Accounting Guidance Pending Adoption New Accounting Guidance Pending Adoption (Details) $ in Millions	Mar. 31, 2018USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated Impact of Adoption of ASU 2018-02	$ 50
LG And E And KU Energy LLC [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated Impact of Adoption of ASU 2018-02	$ 18