Stockholders' Equity (Preferred Stock Issued and Outstanding) (Details) - USD ($) $ / shares in Units, $ in Millions		6 Months Ended
		Jun. 30, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Shares issued (in shares)		1,429,784	1,435,000
Shares outstanding (in shares)		1,429,784	1,435,000
Carrying value	[1]	$ 9,191	$ 9,706
Series D Preferred Stock [Member]
Class of Stock [Line Items]
Shares issued (in shares)		750,000	750,000
Shares outstanding (in shares)		750,000	750,000
Liquidation preference per share (in USD per share)		$ 1,000
Carrying value		$ 728	$ 728
Dividend rate in effect		5.95%
Series J Preferred Stock [Member]
Class of Stock [Line Items]
Shares issued (in shares)		600,000	600,000
Shares outstanding (in shares)		600,000	600,000
Liquidation preference per share (in USD per share)		$ 1,000
Carrying value		$ 584	$ 584
Dividend rate in effect		4.45%
Series F Preferred Stock [Member]
Class of Stock [Line Items]
Shares issued (in shares)		4,883	5,000
Shares outstanding (in shares)		4,883	5,000
Liquidation preference per share (in USD per share)		$ 100,000
Carrying value		$ 481	$ 492
Dividend rate in effect		5.00%
Series F Preferred Stock [Member] | LIBOR [Member]
Class of Stock [Line Items]
Dividend term		3 months
Floating annual rate		2.575%
Series G Preferred Stock [Member]
Class of Stock [Line Items]
Shares issued (in shares)		24,580	25,000
Shares outstanding (in shares)		24,580	25,000
Liquidation preference per share (in USD per share)		$ 100,000
Carrying value		$ 2,428	$ 2,470
Dividend rate in effect		5.375%
Dividend term		5 years
Series G Preferred Stock [Member] | Treasury Rate [Member]
Class of Stock [Line Items]
Dividend term		5 years
Floating annual rate		4.971%
Series H Preferred Stock [Member]
Class of Stock [Line Items]
Shares issued (in shares)		22,267	25,000
Shares outstanding (in shares)		22,267	25,000
Liquidation preference per share (in USD per share)		$ 100,000
Carrying value		$ 2,200	$ 2,470
Dividend rate in effect		4.00%
Dividend term		10 years
Series H Preferred Stock [Member] | Treasury Rate [Member]
Class of Stock [Line Items]
Dividend term		10 years
Floating annual rate		3.079%
Series I Preferred Stock [Member]
Class of Stock [Line Items]
Shares issued (in shares)		20,554	22,500
Shares outstanding (in shares)		20,554	22,500
Liquidation preference per share (in USD per share)		$ 100,000
Carrying value		$ 2,030	$ 2,222
Dividend rate in effect		4.00%
Dividend term		5 years
Series I Preferred Stock [Member] | Treasury Rate [Member]
Class of Stock [Line Items]
Dividend term		5 years
Floating annual rate		3.168%
Series K Preferred Stock [Member]
Class of Stock [Line Items]
Shares issued (in shares)		7,500	7,500
Shares outstanding (in shares)		7,500	7,500
Liquidation preference per share (in USD per share)		$ 100,000
Carrying value		$ 740	$ 740
Dividend rate in effect		5.00%
Series K Preferred Stock [Member] | Treasury Rate [Member]
Class of Stock [Line Items]
Dividend term		5 years
Floating annual rate		3.256%

[1] Certain prior year amounts have been reclassified to conform to the current year presentation. See Note 1 for additional information.