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.