Regulatory Capital Requirements (Details) $ in Millions	9 Months Ended
	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Senior preferred stock	$ 120,836	$ 120,836
Net worth	73,700
Shortfall of available capital	246,000
Adjusted total capital requirement (including buffers)	187,000
Adjusted total assets	4,560,000
Risk-weighted assets	1,346,000
Total capital
Available Capital (Deficit)	(38,000)
Minimum Capital Requirement	108,000
Total Capital Requirement (including Buffers)	$ 108,000
Available Capital (Deficit) Ratio	(0.028)
Minimum Capital Ratio Requirement	0.080
Total Capital Requirement Ratio (including Buffers)	0.080
Common equity tier 1 capital
Available Capital (Deficit)	$ (78,000)
Minimum Capital Requirement	61,000
Total Capital Requirement (including Buffers)	$ 140,000
Available Capital (Deficit) Ratio	(0.058)
Minimum Capital Ratio Requirement	0.045
Total Capital Requirement Ratio (including Buffers)	0.104
Tier 1 capital
Available Capital (Deficit)	$ (59,000)
Minimum Capital Requirement	81,000
Total Capital Requirement (including Buffers)	$ 160,000
Available Capital (Deficit) Ratio	(0.044)
Minimum Capital Ratio Requirement	0.060
Total Capital Requirement Ratio (including Buffers)	0.119
Adjusted total capital
Available Capital (Deficit)	$ (59,000)
Minimum Capital Requirement	108,000
Total Capital Requirement (including Buffers)	$ 187,000
Available Capital (Deficit) Ratio	(0.044)
Minimum Capital Ratio Requirement	0.080
Total Capital Requirement Ratio (including Buffers)	0.139
Core capital
Available Capital (Deficit)	$ (47,000)
Minimum Capital Requirement	114,000
Total Capital Requirement (including Buffers)	$ 114,000
Available Capital (Deficit) Ratio	(0.010)
Minimum Capital Ratio Requirement	0.025
Total Capital Requirement Ratio (including Buffers)	0.025
Tier 1 capital
Available Capital (Deficit)	$ (59,000)
Minimum Capital Requirement	114,000
Total Capital Requirement (including Buffers)	$ 137,000
Available Capital (Deficit) Ratio	(0.013)
Minimum Capital Ratio Requirement	0.025
Total Capital Requirement Ratio (including Buffers)	0.030
Deferred tax assets, net	$ 11,885	12,911
Preferred stock	$ 19,130	$ 19,130
Maximum payout ratio	0