Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions						12 Months Ended
	Jan. 30, 2024	Jun. 01, 2020	Sep. 19, 2018	Sep. 15, 2016	Jun. 15, 2015	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2018	Dec. 31, 2021	Sep. 15, 2021	Jun. 15, 2021	Jul. 25, 2017
Stockholders' Equity Note [Abstract]
Subsidiary equity balance						$ 4,100
Class of Stock [Line Items]
Preferred Stock, Shares Issued						200,000	200,000
Series C Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Shares Issued					2,600,000
Preferred Stock, Dividend Rate, Percentage					6.125%
Preferred Stock, Liquidation Preference Per Share					$ 1,000
Preferred Stock, Redemption Price Per Share					$ 1,000
Preferred Stock, Redemption Amount											$ 65
Series D Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Shares Issued				4,000,000
Preferred Stock, Dividend Rate, Percentage				5.375%
Preferred Stock, Liquidation Preference Per Share				$ 1,000
Preferred Stock, Redemption Price Per Share				$ 1,000
Stock repurchase program authorized amount												$ 15
Preferred Stock, Redemption Amount								$ 1		$ 99
Purchase of Preferred Stock Repurchased During Period, Shares								22,000
Series E Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Shares Issued			4,000,000
Preferred Stock, Dividend Rate, Percentage	5.875%		5.875%
Preferred Stock, Liquidation Preference Per Share			$ 1,000
Preferred Stock, Redemption Price Per Share			$ 1,000
Preferred Stock, Participation Rights			Dividends on the Series E Preferred Stock are payable quarterly in arrears only when, as and if declared by the Board of Directors at a rate per annum equal to 5.875%.
Preferred Stock, Dividend Payment Terms			Shares of the Series E Preferred Stock have priority over the Corporation’s common stock with regard to the payment of dividends and distributions upon liquidation, dissolution or winding up. As such, the Corporation may not pay dividends on or repurchase, redeem, or otherwise acquire for consideration shares of its common stock unless dividends for the Series E Preferred Stock have been declared for that period, and sufficient funds have been set aside to make payment.
Preferred Stock, Redemption Terms			The Series E Preferred Stock may be redeemed by the Corporation at its option (i) either in whole or in part, from time to time, on any dividend payment date on or after the dividend payment date occurring on December 15, 2023, or (ii) in whole but not in part, at any time within 90 days following certain regulatory capital treatment events, in each case at a redemption price of $1,000 per share (equivalent to $25 per depositary share), plus any applicable dividends.
Preferred Stock, Voting Rights			Except in certain limited circumstances, the Series E Preferred Stock does not have any voting rights.
Series F Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued		4,000,000
Preferred Stock, Dividend Rate, Percentage		5.625%
Preferred Stock, Liquidation Preference Per Share		$ 1,000
Preferred Stock, Redemption Price Per Share		$ 1,000
Preferred Stock, Participation Rights		Dividends on the Series F Preferred Stock are payable quarterly in arrears only when, as and if declared by the Board of Directors at a rate per annum equal to 5.625%.
Preferred Stock, Dividend Payment Terms		Shares of the Series F Preferred Stock have priority over the Corporation’s common stock with regard to the payment of dividends and distributions upon liquidation, dissolution or winding up. As such, the Corporation may not pay dividends on or repurchase, redeem, or otherwise acquire for consideration shares of its common stock unless dividends for the Series F Preferred Stock have been declared for that period, and sufficient funds have been set aside to make payment.
Preferred Stock, Redemption Terms		The Series F Preferred Stock may be redeemed by the Corporation at its option (i) either in whole or in part, from time to time, on any dividend payment date on or after the dividend payment date occurring on September 15, 2025, or (ii) in whole but not in part, at any time within 90 days following certain regulatory capital treatment events, in each case at a redemption price of $1,000 per share (equivalent to $25 per depositary share), plus any applicable dividends.
Preferred Stock, Voting Rights		Except in certain limited circumstances, the Series F Preferred Stock does not have any voting rights.
Treasury Stock
Class of Stock [Line Items]
Stock repurchase program authorized amount						$ 0			$ 100
Purchase of Preferred Stock Repurchased During Period, Shares						0
Common Stock [Member]
Class of Stock [Line Items]
Payments Related to Tax Withholding for Share-based Compensation						$ 7	$ 6
Shares Paid for Tax Withholding for Share Based Compensation						297,564	267,605
Minimum tax withholding settlement average cost per share (in usd per share)						$ 22.16	$ 24.22
Remaining authorized repurchase amount						$ 80