v3.19.3.a.u2

Summary of Significant Accounting Policies Intangible Assets by Component (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Assets, Gross | $ 933 | $ 1,031 |
Finite-Lived Intangible Assets, Accumulated Amortization | 593 | 619 |
Finite-Lived Intangible Assets, Net | 340 | 412 |
Amortization of Intangible Assets | 72 | 100 | $ 175
Acquired contracts [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Assets, Gross | $ 444 | 458 |
Acquired contracts [Member] | Minimum [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 0 years |  |
Acquired contracts [Member] | Maximum [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 9 years |  |
Customer Relationships [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Assets, Gross | $ 445 | 445 |
Customer Relationships [Member] | Minimum [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 7 years |  |
Customer Relationships [Member] | Maximum [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 14 years |  |
Trademarks and Trade Names [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Assets, Gross | $ 40 | 40 |
Trademarks and Trade Names [Member] | Minimum [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 15 years |  |
Trademarks and Trade Names [Member] | Maximum [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 15 years |  |
Other Intangible Assets [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Assets, Gross | $ 4 | $ 88 |
Other Intangible Assets [Member] | Minimum [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 39 years |  |
Other Intangible Assets [Member] | Maximum [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-Lived Intangible Asset, Useful Life | 44 years |  |

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