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Equity And Earnings Per Share (Basic Table) (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Basic earnings per share: |  |  |  |
Net income available for common stockholders | $ 36 | $ 39 | $ 117 | $ 126
Weighted average shares of common stock outstanding: |  |  |  |
Weighted Average Number of Shares Outstanding, Basic | 76,742,789 | 74,649,469 | 75,910,080 | 72,879,007
Basic earnings per share | $ 0.46 | $ 0.52 | $ 1.54 | $ 1.73
Common Class A |  |  |  |
Weighted average shares of common stock outstanding: |  |  |  |
Weighted Average Number of Shares Outstanding, Basic | 76,742,689 | 74,649,369 | 75,909,980 | 72,878,907
Common Class B |  |  |  |
Weighted average shares of common stock outstanding: |  |  |  |
Weighted Average Number of Shares Outstanding, Basic | 100 | 100 | 100 | 100

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