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Equity And Earnings Per Share (Diluted Table) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Diluted earnings per share:
Net income available for common stockholders	$ 107	$ 46
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	90,789,321	76,751,168
Potentially dilutive common shares:
Issuable pursuant to employee incentive plans	976,821	817,296
Weighted Average Number of Shares Outstanding, Diluted	91,766,142	77,568,464
Earnings Per Share, Diluted	$ 1.16	$ 0.60
Common Class A [Member]
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	90,789,221	76,751,068
Common Class B [Member]
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	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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