v3.19.3.a.u2

Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Mar. 08, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Sale of Stock, Price Per Share |  |  |  | $ 15.25
Payments for Repurchase of Common Stock | $ 0 | $ 79 | $ 0 |
Share-based Payment Arrangement, Accelerated Cost |  | 35 |  |
Stock-based compensation expense |  | 41 | 36 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value |  | 11 | 0 |
Option exercises |  | 0 | 0 |
Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value |  | 88 | 23 |
Performance Shares [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Share-based Liabilities Paid |  | 25 |  |
Share-based Compensation Arrangement by Liability Classified Share-based Payment Awards Accelerated Compensation Cost |  | 16 |  |
Allocated Share Based Compensation Expense Liability Classified Share-Based Awards |  | $ 16 | $ 6 |

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