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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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