Netting Arrangements (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Assets:
Derivative assets, gross amount	$ 314	$ 326
Derivative assets, gross amount offset	(164)	(154)
Derivative assets, net amount presented in our condensed consolidated balance sheets	150	172
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	(55)	(50)
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	(1)	(12)
Derivative assets, net amount	94	110
Securities purchased under agreements to resell, gross amount	81,550	69,415
Securities purchased under agreements to resell, gross amount offset	0	0
Securities purchased under agreements to resell, under master netting arrangements,	81,550	69,415
Securities purchased under agreements to resell, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	0	0
Securities purchased under agreements to resell, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	(81,550)	(69,415)
Securities purchased under agreements to resell, net amount	0	0
Total assets, gross amount	81,864	69,741
Total assets, gross amount offset	(164)	(154)
Total assets, net amount presented in our condensed consolidated balance sheets	81,700	69,587
Total assets, under the master netting arrangements, not offset in our consolidated balance sheets, financial instruments	(55)	(50)
Total assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	(81,551)	(69,427)
Total assets, net amount	94	110
Liabilities:
Total liabilities, gross amount	(4,153)	(4,764)
Total liabilities, gross amount offset	3,910	4,662
Total liabilities, net amount presented in our condensed consolidated balance sheets	(243)	(102)
Total liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	55	50
Total liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	97	7
Total liabilities, net amount	(91)	(45)
Mortgage commitment derivatives
Assets:
Derivative assets, gross amount	100	89
Derivative assets, gross amount offset	0	0
Derivative assets, net amount presented in our condensed consolidated balance sheets	100	89
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	(55)	(50)
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	(1)	(12)
Derivative assets, net amount	44	27
Liabilities:
Derivative liabilities, gross amount	(143)	(78)
Derivative liabilities, gross amount offset	0	0
Derivative liabilities, net amount presented in our condensed consolidated balance sheets	(143)	(78)
Derivative liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	55	50
Derivative liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	0	7
Derivative liabilities, net amount	(88)	(21)
OTC risk management derivatives | Risk Management Derivatives
Assets:
Derivative assets, gross amount	214	237
Derivative assets, gross amount offset	(165)	(234)
Derivative assets, net amount presented in our condensed consolidated balance sheets	49	3
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	0	0
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	0	0
Derivative assets, net amount	49	3
Liabilities:
Derivative liabilities, gross amount	(4,010)	(4,686)
Derivative liabilities, gross amount offset	4,007	4,662
Derivative liabilities, net amount presented in our condensed consolidated balance sheets	(3)	(24)
Derivative liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	0	0
Derivative liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	0	0
Derivative liabilities, net amount	(3)	(24)
Cleared risk management derivatives | Risk Management Derivatives
Assets:
Derivative assets, gross amount	0	0
Derivative assets, gross amount offset	1	80
Derivative assets, net amount presented in our condensed consolidated balance sheets	1	80
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	0	0
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	0	0
Derivative assets, net amount	1	80
Liabilities:
Derivative liabilities, gross amount	0	0
Derivative liabilities, gross amount offset	(97)	0
Derivative liabilities, net amount presented in our condensed consolidated balance sheets	(97)	0
Derivative liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	0	0
Derivative liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	97	0
Derivative liabilities, net amount	$ 0	$ 0