Intangible Assets

12 Months Ended

Dec. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

14. Goodwill and Intangible Assets

Intangible assets are being amortized on a straight-line basis over their estimated useful lives and are detailed below:

		As of December 31, 2021						As of December 31, 2020
(In millions)	Useful Lives	Gross Carrying Amount		Accumulated Amortization		Net Amount		Gross Carrying Amount		Accumulated Impairment		Accumulated Amortization		Net Amount
Customer relationships	22 Years	$	413	$	18	$	395	$	132	$	55	$	77	$	—
Patents	5-15 Years	17		11		6		22		7		10		5
Energy Contract	2 Years	54		11		43		54		—		5		49
Other	4-15 Years	—		—		—		14		5		9		—
Total amortizable intangible assets		$	484	$	40	$	444	$	222	$	67	$	101	$	54

Amortization expense was $26 million and $8 million for years ended December 31, 2021 and December 31, 2020, respectively. We expect approximately $142 million in annual amortization expense through 2026 and approximately $301 million in remaining amortization expense thereafter.

The carrying amount of acquired water rights with indefinite lives as of December 31, 2021 and December 31, 2020 totaled $75 million.

Below is a summary of goodwill by segment for the twelve months ended December 31, 2021:

(In millions)	Flat-Rolled		Mini Mill		USSE		Tubular		Total
Balance at December 31, 2020	$	—	$	—	$	4	$	—	$	4
Additions	—		916		—		—		916
Balance at December 31, 2021	$	—	$	916	$	4	$	—	$	920