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Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | $ 2,741 | $ 2,786
Accumulated Amortization and Impairment | 2,212 | 2,146
Total | 529 | 640
Estimated amortization for intangible assets |  |
Remainder of 2021 | 34 |
2022 | 101 |
2023 | 90 |
2024 | 73 |
2025 | 59 |
2026 | 37 |
Thereafter | 135 |
Total | 529 | 640
Customer-related and contract-based |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 2,314 | 2,337
Accumulated Amortization and Impairment | 1,842 | 1,775
Total | 472 | 562
Estimated amortization for intangible assets |  |
Total | 472 | 562
Tradenames |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 14 | 14
Accumulated Amortization and Impairment | 13 | 13
Total | 1 | 1
Estimated amortization for intangible assets |  |
Total | 1 | 1
Technology and other |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 413 | 435
Accumulated Amortization and Impairment | 357 | 358
Total | 56 | 77
Estimated amortization for intangible assets |  |
Total | $ 56 | $ 77

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