Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Summary of Significant Accounting Policies [Line Items]

Schedule of Utility Revenue

For the years ended December 31, the Statements of Income "Operating Revenues" line item contains revenue from the following: 

	2017		2016		2015
Domestic electric and gas revenues (a)	$	5,351	$	5,297	$	5,239
U.K. operating revenues (b)	2,091		2,207		2,410
Domestic - other	5		13		20
Total	$	7,447	$	7,517	$	7,669

(a) Represents revenues from cost-based rate-regulated generation, transmission and/or distribution in Pennsylvania, Kentucky, Virginia and Tennessee, including regulated wholesale revenue.

(b) Primarily represents regulated electricity distribution revenues from the operation of WPD's distribution networks.

Schedule of Valuation and Qualifying Accounts Disclosure

The changes in the allowance for doubtful accounts were: 

			Additions
	Balance at Beginning of Period		Charged to Income		Charged to Other Accounts			Deductions (a)		Balance at End of Period
PPL
2017	$	54	$	28	$	(1	)	$	30	$	51
2016	41		44		—			31		54
2015	44		49		(2		)	50		41
PPL Electric
2017	$	28	$	18	$	—		$	22	$	24
2016	16		35		—			23		28
2015	17		39		—			40		16

			Additions
	Balance at Beginning of Period		Charged to Income		Charged to Other Accounts			Deductions (a)		Balance at End of Period
LKE
2017	$	24	$	8	$	(1	)	$	6	$	25
2016	23		8		—			7		24
2015	25		9		(2		)	9		23
LG&E
2017	$	2	$	2	$	(1	)	$	2	$	1
2016	1		2		1			2		2
2015	2		2		—			3		1
KU
2017	$	2	$	4	$	(1	)	$	4	$	1
2016	2		4		—			4		2
2015	2		5		—			5		2

(a) Primarily related to uncollectible accounts written off.

Schedule of Restricted Cash and Cash Equivalents

At December 31, the balances of restricted cash and cash equivalents included the following: 

	PPL				PPL Electric
	2017		2016		2017		2016
Low carbon network fund (a)	$	17	$	17	$	—	$	—
Other	9		9		2		2
Total	$	26	$	26	$	2	$	2

(a) Funds received by WPD, which are to be spent on approved initiatives to support a low carbon environment.

Weighted-average Rates of Depreciation

Following are the weighted-average annual rates of depreciation, for regulated utility plant, for the years ended December 31:

	2017		2016		2015
PPL	2.65	%	2.73	%	2.57	%
PPL Electric	2.86	%	2.63	%	2.46	%
LKE	3.64	%	3.69	%	3.69	%
LG&E	3.63	%	3.58	%	3.65	%
KU	3.66	%	3.77	%	3.71	%

Schedule of Utility Inventory

"Fuel, materials and supplies" on the Balance Sheets consisted of the following at December 31:

	PPL				LKE				LG&E				KU
	2017		2016		2017		2016		2017		2016		2017		2016
Fuel	$	107	$	158	$	107	$	158	$	45	$	60	$	62	$	98
Natural gas stored underground	43		42		43		42		43		42		—		—
Materials and supplies	170		156		104		97		43		41		61		56
Total	$	320	$	356	$	254	$	297	$	131	$	143	$	123	$	154

PPL Electric Utilities Corp [Member]

Summary of Significant Accounting Policies [Line Items]

Schedule of Restricted Cash and Cash Equivalents

At December 31, the balances of restricted cash and cash equivalents included the following: 

	PPL				PPL Electric
	2017		2016		2017		2016
Low carbon network fund (a)	$	17	$	17	$	—	$	—
Other	9		9		2		2
Total	$	26	$	26	$	2	$	2

(a) Funds received by WPD, which are to be spent on approved initiatives to support a low carbon environment.

Intercompany tax receivables (payables)

At December 31, the following intercompany tax receivables (payables) were recorded:

	2017			2016
PPL Electric	$	61		$	13
LKE	(23		)	1
LG&E	—			(18		)
KU	—			(29		)

LG And E And KU Energy LLC [Member]

Summary of Significant Accounting Policies [Line Items]

Intercompany tax receivables (payables)

At December 31, the following intercompany tax receivables (payables) were recorded:

	2017			2016
PPL Electric	$	61		$	13
LKE	(23		)	1
LG&E	—			(18		)
KU	—			(29		)

Schedule of Utility Inventory

"Fuel, materials and supplies" on the Balance Sheets consisted of the following at December 31:

	PPL				LKE				LG&E				KU
	2017		2016		2017		2016		2017		2016		2017		2016
Fuel	$	107	$	158	$	107	$	158	$	45	$	60	$	62	$	98
Natural gas stored underground	43		42		43		42		43		42		—		—
Materials and supplies	170		156		104		97		43		41		61		56
Total	$	320	$	356	$	254	$	297	$	131	$	143	$	123	$	154

Louisville Gas And Electric Co [Member]

Summary of Significant Accounting Policies [Line Items]

Intercompany tax receivables (payables)

At December 31, the following intercompany tax receivables (payables) were recorded:

	2017			2016
PPL Electric	$	61		$	13
LKE	(23		)	1
LG&E	—			(18		)
KU	—			(29		)

Schedule of Utility Inventory

"Fuel, materials and supplies" on the Balance Sheets consisted of the following at December 31:

	PPL				LKE				LG&E				KU
	2017		2016		2017		2016		2017		2016		2017		2016
Fuel	$	107	$	158	$	107	$	158	$	45	$	60	$	62	$	98
Natural gas stored underground	43		42		43		42		43		42		—		—
Materials and supplies	170		156		104		97		43		41		61		56
Total	$	320	$	356	$	254	$	297	$	131	$	143	$	123	$	154

Kentucky Utilities Co [Member]

Summary of Significant Accounting Policies [Line Items]

Intercompany tax receivables (payables)

At December 31, the following intercompany tax receivables (payables) were recorded:

	2017			2016
PPL Electric	$	61		$	13
LKE	(23		)	1
LG&E	—			(18		)
KU	—			(29		)

Schedule of Utility Inventory

"Fuel, materials and supplies" on the Balance Sheets consisted of the following at December 31:

	PPL				LKE				LG&E				KU
	2017		2016		2017		2016		2017		2016		2017		2016
Fuel	$	107	$	158	$	107	$	158	$	45	$	60	$	62	$	98
Natural gas stored underground	43		42		43		42		43		42		—		—
Materials and supplies	170		156		104		97		43		41		61		56
Total	$	320	$	356	$	254	$	297	$	131	$	143	$	123	$	154