Consolidated Statements of Changes in Equity (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash dividends declared on Common Shares (in usd per share)	$ 0.185	$ 0.185
Net income (loss)	$ 622	$ 146
Retained Earnings
Net income (loss)	$ 622	$ 146
Series D Preferred Stock
Cash dividends declared on Preferred Stock (in usd per share)	$ 12.50	$ 12.50
Series E Preferred Stock
Cash dividends declared on Preferred Stock (in usd per share)	0.382813	0.382813
Series F Preferred Stock
Cash dividends declared on Preferred Stock (in usd per share)	0.353125	0.353125
Series G Preferred Stock
Cash dividends declared on Preferred Stock (in usd per share)	$ 0.351563	$ 0.351563