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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, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Basic earnings per share: |  |  |  |
Net income available for common stockholders | $ 46 | $ 36 | $ 124 | $ 117
Weighted average shares of common stock outstanding: |  |  |  |
Weighted Average Number of Shares Outstanding, Basic | 78,509,625 | 76,742,789 | 77,543,008 | 75,910,080
Basic earnings per share | $ 0.59 | $ 0.46 | $ 1.60 | $ 1.54
Common Class A [Member] |  |  |  |
Weighted average shares of common stock outstanding: |  |  |  |
Weighted Average Number of Shares Outstanding, Basic | 78,509,525 | 76,742,689 | 77,542,908 | 75,909,980
Common Class B [Member] |  |  |  |
Weighted average shares of common stock outstanding: |  |  |  |
Weighted Average Number of Shares Outstanding, Basic | 100 | 100 | 100 | 100

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