Property, Equipment, and Capitalized Software, Net - Depreciation and Amortization (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Recorded in depreciation and amortization:
Amortization of intangible assets	$ 49	$ 15	$ 18
Amortization of capitalized software	41	38	33
Amortization of finance leases	25	19	17
Depreciation and amortization of furniture, equipment, building, and improvements	16	16	21
Total depreciation and amortization recognized	$ 131	$ 88	$ 89

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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