Intangible Assets

12 Months Ended

Dec. 31, 2020

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

Note 11: Intangible Assets

Intangible assets and related amortization expense were as follows:

	December 31, 2020
($ in millions)	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Management agreements	$	89	$	(51	)	$	38
Capitalized software		94	$	(51	)		43
	$	183	$	(102	)	$	81

	December 31, 2019
($ in millions)	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Management agreements	$	88	$	(46	)	$	42
Capitalized software		73		(38	)		35
	$	161	$	(84	)	$	77

Amortization expense on intangible assets was $15 million, $9 million, and $10 million for the years ended December 31, 2020, 2019 and 2018, respectively. As of December 31, 2020, the weighted average amortization period on management agreements was 12 years and capitalized software was 2.5 years.

As of December 31, 2020, we estimated our future amortization expense for our amortizing intangible assets to be as follows:

($ in millions)	Future Amortization Expense
Year
2021	$	23
2022		19
2023		12
2024		3
2025		3
Thereafter		21
	$	81