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Equity And Earnings Per Share (Basic Table) (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015
Basic earnings per share: |  |  |  |
Net income available for common stockholders | $ 27 | $ 23 | $ 60 | $ 10
Weighted average shares of common stock outstanding: |  |  |  |
Weighted Average Number of Shares Outstanding, Basic | 64,967,364 | 59,481,778 | 64,476,421 | 58,980,348
Basic earnings per share | $ 0.41 | $ 0.38 | $ 0.93 | $ 0.17
Common Class A |  |  |  |
Weighted average shares of common stock outstanding: |  |  |  |
Weighted Average Number of Shares Outstanding, Basic | 64,967,264 | 59,481,678 | 64,476,321 | 58,980,248
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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