Netting Arrangements (Details) - USD ($)	Jun. 30, 2024	Dec. 31, 2023
Assets:
Derivative assets, gross amount	$ 442,000,000	$ 440,000,000
Derivative assets, gross amount offset	(290,000,000)	(283,000,000)
Derivative assets, net amount presented in our condensed consolidated balance sheets	152,000,000	157,000,000
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	(50,000,000)	(23,000,000)
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	(1,000,000)	(9,000,000)
Derivative assets, net amount	101,000,000	125,000,000
Securities purchased under agreements to resell, gross amount	70,200,000,000	65,425,000,000
Securities purchased under agreements to resell, gross amount offset	0	0
Securities purchased under agreements to resell, under master netting arrangements	70,200,000,000	65,425,000,000
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	(70,200,000,000)	(65,425,000,000)
Securities purchased under agreements to resell, net amount	0	0
Total assets, gross amount	70,642,000,000	65,865,000,000
Total assets, gross amount offset	(290,000,000)	(283,000,000)
Total assets, net amount presented in our condensed consolidated balance sheets	70,352,000,000	65,582,000,000
Total assets, under the master netting arrangements, not offset in our consolidated balance sheets, financial instruments	(50,000,000)	(23,000,000)
Total assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	(70,201,000,000)	(65,434,000,000)
Total assets, net amount	101,000,000	125,000,000
Liabilities:
Total liabilities, gross amount	(3,092,000,000)	(3,327,000,000)
Total liabilities, gross amount offset	3,026,000,000	3,200,000,000
Total liabilities, net amount presented in our condensed consolidated balance sheets	(66,000,000)	(127,000,000)
Total liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	50,000,000	23,000,000
Total liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	7,000,000	80,000,000
Total liabilities, net amount	(9,000,000)	(24,000,000)
Securities received as collateral	70,200,000,000	65,500,000,000
Fair value of securities received as collateral that can be resold or repledged	55,300,000,000	55,400,000,000
Fair value of securities received as collateral that have been resold or repledged	0	0
Derivative assets not subject to enforceable master netting arrangements	67,000,000	45,000,000
Derivative liabilities not subject to enforceable master netting arrangements	(15,000,000)	(13,000,000)
Securities purchased under agreements to resell	27,650,000,000	30,700,000,000
Cash and Cash Equivalents
Liabilities:
Securities purchased under agreements to resell	28,200,000,000	21,800,000,000
Restricted Cash and Cash Equivalent
Liabilities:
Securities purchased under agreements to resell	14,400,000,000	12,900,000,000
Asset pledged as collateral with right to sell or repledge
Assets:
Total assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	(2,000,000,000.0)	(2,200,000,000)
Mortgage commitment derivatives
Assets:
Derivative assets, gross amount	66,000,000	112,000,000
Derivative assets, gross amount offset	0	0
Derivative assets, net amount presented in our condensed consolidated balance sheets	66,000,000	112,000,000
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	(50,000,000)	(23,000,000)
Derivative assets, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	(1,000,000)	(9,000,000)
Derivative assets, net amount	15,000,000	80,000,000
Liabilities:
Derivative liabilities, gross amount	(65,000,000)	(104,000,000)
Derivative liabilities, gross amount offset	0	0
Derivative liabilities, net amount presented in our condensed consolidated balance sheets	(65,000,000)	(104,000,000)
Derivative liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, financial instruments	50,000,000	23,000,000
Derivative liabilities, under master netting arrangements, amounts not offset in our condensed consolidated balance sheets, collateral	7,000,000	77,000,000
Derivative liabilities, net amount	(8,000,000)	(4,000,000)
OTC risk management derivatives | Risk Management Derivatives
Assets:
Derivative assets, gross amount	376,000,000	328,000,000
Derivative assets, gross amount offset	(342,000,000)	(294,000,000)
Derivative assets, net amount presented in our condensed consolidated balance sheets	34,000,000	34,000,000
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	34,000,000	34,000,000
Liabilities:
Derivative liabilities, gross amount	(3,027,000,000)	(3,223,000,000)
Derivative liabilities, gross amount offset	3,026,000,000	3,203,000,000
Derivative liabilities, net amount presented in our condensed consolidated balance sheets	(1,000,000)	(20,000,000)
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	(1,000,000)	(20,000,000)
Cleared risk management derivatives | Risk Management Derivatives
Assets:
Derivative assets, gross amount	0	0
Derivative assets, gross amount offset	52,000,000	11,000,000
Derivative assets, net amount presented in our condensed consolidated balance sheets	52,000,000	11,000,000
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	52,000,000	11,000,000
Liabilities:
Derivative liabilities, gross amount	0	0
Derivative liabilities, gross amount offset	0	(3,000,000)
Derivative liabilities, net amount presented in our condensed consolidated balance sheets	0	(3,000,000)
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	3,000,000
Derivative liabilities, net amount	$ 0	$ 0