Goodwill and Other Intangible Assets (Tables)

The changes in the carrying amount of goodwill by segment were:



	U.K. Regulated					Kentucky Regulated				Corporate and Other				Total
	U.K. Regulated					Kentucky Regulated				Corporate and Other				Total
	2018			2017		2018		2017		2018		2017		2018			2017
Balance at beginning of period (a)	$	2,596		$	2,398	$	662	$	662	$	—	$	—	$	3,258		$	3,060
Effect of foreign currency exchange rates	(149		)	198		—		—		—		—		(149		)	198
Goodwill recognized during the period (b)	—			—		—		—		53		—		53			—
Balance at end of period (a)	$	2,447		$	2,596	$	662	$	662	$	53	$	—	$	3,162		$	3,258


(a)	There were no accumulated impairment losses related to goodwill.


(b)	Recognized as a result of the acquisition of Safari Energy.

The gross carrying amount and the accumulated amortization of other intangible assets were:



	December 31, 2018				December 31, 2017
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Subject to amortization:
Contracts (a)	$	137	$	75	$	138	$	67
Land rights and easements	418		128		382		120
Licenses and other	21		1		8		3
Total subject to amortization	576		204		528		190

Not subject to amortization due to indefinite life:
Land rights and easements	339		—		359		—
Other	6		—		—		—
Total not subject to amortization due to indefinite life	345		—		359		—
Total	$	921	$	204	$	887	$	190


(a)	Gross carrying amount in 2018 and 2017 includes the fair value at the acquisition date of the OVEC power purchase contract with terms favorable to market recognized as a result of the 2010 acquisition of LKE by PPL.



Amortization Expense was as follows:
	2018		2017		2016
Intangible assets with no regulatory offset	$	7	$	6	$	6
Intangible assets with regulatory offset	8		9		24
Total	$	15	$	15	$	30

Amortization expense for each of the next five years is estimated to be:



	2019		2020		2021		2022		2023
Intangible assets with no regulatory offset	$	7	$	7	$	7	$	7	$	7
Intangible assets with regulatory offset	9		8		8		8		8
Total	$	16	$	15	$	15	$	15	$	15

The gross carrying amount and the accumulated amortization of other intangible assets were:



	December 31, 2018				December 31, 2017
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Subject to amortization:
Land rights and easements	$	363	$	121	$	361	$	117
Licenses and other	2		1		3		1
Total subject to amortization	365		122		364		118

Not subject to amortization due to indefinite life:
Land rights and easements	17		—		13		—
Total	$	382	$	122	$	377	$	118

The gross carrying amount and the accumulated amortization of other intangible assets were:



	December 31, 2018				December 31, 2017
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Subject to amortization:
Land rights and easements	$	21	$	3	$	21	$	3
OVEC power purchase agreement (a)	126		66		126		58
Total subject to amortization	$	147	$	69	$	147	$	61


(a)	Gross carrying amount represents the fair value at the acquisition date of the OVEC power purchase contract recognized as a result of the 2010 acquisition by PPL. An offsetting regulatory liability was recorded related to this contract, which is being amortized over the same period as the intangible asset, eliminating any income statement impact. See Note 7 for additional information.

Amortization expense was as follows:



	2018		2017		2016
Intangible assets with no regulatory offset	$	—	$	—	$	1
Intangible assets with regulatory offset	8		9		24
Total	$	8	$	9	$	25

Amortization expense for each of the next five years is estimated to be:



	2019		2020		2021		2022		2023
Intangible assets with regulatory offset	$	9	$	8	$	8	$	8	$	8

The gross carrying amount and the accumulated amortization of other intangible assets were:



	December 31, 2018				December 31, 2017
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Subject to amortization:
Land rights and easements	$	7	$	1	$	7	$	1
OVEC power purchase agreement (a)	87		46		87		40
Total subject to amortization	$	94	$	47	$	94	$	41


(a)	Gross carrying amount represents the fair value at the acquisition date of the OVEC power purchase contract recognized as a result of the 2010 acquisition by PPL. An offsetting regulatory liability was recorded related to this contract, which is being amortized over the same period as the intangible asset, eliminating any income statement impact. See Note 7 for additional information.

Amortization expense was as follows:



	2018		2017		2016
Intangible assets with regulatory offset	$	6	$	6	$	13

Amortization expense for each of the next five years is estimated to be:



	2019		2020		2021		2022		2023
Intangible assets with regulatory offset	$	6	$	6	$	6	$	6	$	6

The gross carrying amount and the accumulated amortization of other intangible assets were:



	December 31, 2018				December 31, 2017
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Subject to amortization:
Land rights and easements	$	14	$	2	$	14	$	2
OVEC power purchase agreement (a)	39		20		39		18
Total subject to amortization	$	53	$	22	$	53	$	20


(a)	Gross carrying amount represents the fair value at the acquisition date of the OVEC power purchase contract recognized as a result of the 2010 acquisition by PPL. An offsetting regulatory liability was recorded related to this contract, which is being amortized over the same period as the intangible asset, eliminating any income statement impact. See Note 7 for additional information.

Amortization expense was as follows:



	2018		2017		2016
Intangible assets with no regulatory offset	$	—	$	—	$	1
Intangible assets with regulatory offset	2		3		11
Total	$	2	$	3	$	12

Amortization expense for each of the next five years is estimated to be:



	2019		2020		2021		2022		2023
Intangible assets with regulatory offset	$	3	$	2	$	2	$	2	$	2