Derivatives Derivatives - Cumulative Basis Adjustment due to Fair Value Hedges (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Cumulative Basis Adjustments Due to Fair Value Hedging [Line Items]
Carrying amount debt hedged liability	$ (78,921)	$ (107,241)
Total basis adjustment cumulative amount for hedged liability	2,182	4,050
Hedged Asset, Fair Value Hedge, Portfolio Layer, Cumulative Increase (Decrease)	(300)	(700)
Basis adjustment amount for hedged liability - discontinued hedge	15	19
Mortgage loans held-for-investment
Cumulative Basis Adjustments Due to Fair Value Hedging [Line Items]
Carrying amount mortgage loans held-for-investment hedged asset	1,098,249	1,117,060
Total basis adjustment cumulative amount for hedged asset	(2,336)	(3,909)
Hedged Asset, Fair Value Hedge, Portfolio Layer, Cumulative Increase (Decrease)	(262)	(695)
Basis adjustment amount for hedged asset - discontinued hedge	(2,074)	(3,214)
Closed Portfolio and Beneficial Interest, Portfolio Layer, Amortized Cost	43,348	56,394
Hedged Asset, Fair Value Hedge, Portfolio Layer, Amount	$ 8,435	$ 12,070

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- Definition

Amortized cost of closed portfolio of financial asset and beneficial interest secured by financial instrument, used to designate hedging relationship in which hedged item is expected to be outstanding for designated hedge period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. Excludes cumulative basis adjustment related to foreign exchange risk.

+ References

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Amount of asset hedged in fair value hedging relationship.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of asset hedged in portfolio layer hedging relationship, expected to be remaining at end of hedging relationship.

+ References

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, in portfolio layer hedging relationship.

+ References

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. Excludes cumulative basis adjustment related to foreign exchange risk.

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Amount of liability hedged in fair value hedging relationship.

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

+ References

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