Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Carrying value	$ 2,324	$ 2,324
Preferred stock dividends — Series B
Class of Stock [Line Items]
Carrying value	$ 1,335	$ 1,335
Par value (in dollars per share)	$ 0.01	$ 0.01
Liquidation preference (in dollars per share)	$ 1,000	$ 1,000
Number of shares authorized (in shares)	1,350,000	1,350,000
Number of shares issued (in shares)	1,350,000	1,350,000
Number of shares outstanding (in shares)	1,350,000	1,350,000
Series B Preferred Stock, Prior To May 15, 2026
Class of Stock [Line Items]
Dividend/coupon rate	4.70%	4.70%
Series B Preferred Stock, On And After May 15, 2026 | US Treasury (UST) Interest Rate
Class of Stock [Line Items]
Dividend/coupon rate	3.868%	3.868%
Preferred stock dividends — Series C
Class of Stock [Line Items]
Carrying value	$ 989	$ 989
Par value (in dollars per share)	$ 0.01	$ 0.01
Liquidation preference (in dollars per share)	$ 1,000	$ 1,000
Number of shares authorized (in shares)	1,000,000	1,000,000
Number of shares issued (in shares)	1,000,000	1,000,000
Number of shares outstanding (in shares)	1,000,000	1,000,000
Series C Preferred Stock, Prior To May 15, 2028
Class of Stock [Line Items]
Dividend/coupon rate	4.70%	4.70%
Series C Preferred Stock, On And After May 15, 2028 | US Treasury (UST) Interest Rate
Class of Stock [Line Items]
Dividend/coupon rate	3.481%	3.481%