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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, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Basic earnings per share:
Net income available for common stockholders	$ 32	$ 41	$ 81	$ 87
Weighted average shares of common stock outstanding:
Weighted Average Number of Shares Outstanding, Basic	75,868,349	72,476,729	75,486,825	71,979,104
Basic earnings per share	$ 0.43	$ 0.57	$ 1.08	$ 1.21
Common Class A
Weighted average shares of common stock outstanding:
Weighted Average Number of Shares Outstanding, Basic	75,868,249	72,476,629	75,486,725	71,979,004
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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