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Equity And Earnings Per Share (Diluted Table) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Diluted earnings per share:
Net income available for common stockholders	$ 42	$ 46	$ 241	$ 124
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	96,229,958	78,509,625	92,814,767	77,543,008
Potentially dilutive common shares:
Issuable pursuant to employee incentive plans	760,010	610,923	856,922	700,691
Weighted Average Number of Shares Outstanding, Diluted	96,989,968	79,120,548	93,671,689	78,243,699
Earnings Per Share, Diluted	$ 0.43	$ 0.58	$ 2.58	$ 1.58
Common Class A [Member]
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	96,229,858	78,509,525	92,814,667	77,542,908
Common Class B [Member]
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	100	100	100	100

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

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