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Equity And Earnings Per Share (Basic Table) (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Basic earnings per share: |  |  |
Net income available for common stockholders | $ 161 | $ 169 | $ 76
Weighted average shares of common stock outstanding: |  |  |
Weighted Average Number of Shares Outstanding, Basic | 76,121,570 | 73,438,209 | 69,926,933
Basic earnings per share | $ 2.11 | $ 2.30 | $ 1.09
Common Class A |  |  |
Weighted average shares of common stock outstanding: |  |  |
Weighted Average Number of Shares Outstanding, Basic | 76,121,470 | 73,438,109 | 69,926,833
Common Class B |  |  |
Weighted average shares of common stock outstanding: |  |  |
Weighted Average Number of Shares Outstanding, Basic | 100 | 100 | 100

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