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Segment Information - Schedule of consolidated non-current assets by geographic area (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Long-lived assets, including operating lease ROU assets | $ 1,550 |
Fixed assets, net | 621 | $ 588
U.S. |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Long-lived assets, including operating lease ROU assets | 686 |
Fixed assets, net |  | 288
Americas other than U.S. |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Long-lived assets, including operating lease ROU assets | 145 |
Fixed assets, net |  | 44
United Kingdom |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Long-lived assets, including operating lease ROU assets | 225 |
Fixed assets, net |  | 58
Europe, Middle East, & Africa |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Long-lived assets, including operating lease ROU assets | 319 |
Fixed assets, net |  | 101
Asia Pacific |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Long-lived assets, including operating lease ROU assets | $ 175 |
Fixed assets, net |  | $ 97

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