Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Mortgage and mortgage-related assets	$ 5,944	$ 6,764
Allowance for loan losses and basis in acquired property, net	1,571	2,055
Derivative instruments	766	1,153
Partnership and other equity investments	21	52
Interest-only securities	3,801	3,811
Other, net	617	295
Total deferred tax assets	12,720	14,130
Deferred tax liabilities:
Debt instruments	894	1,104
Valuation allowance	(145)	(115)
Deferred tax assets, net	$ 11,681	$ 12,911