Derivative Instruments and Hedging Activities (Details - Fair Value Hedge) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Total interest income	$ 409	$ 560	$ 852	$ 1,115
Interest Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total interest income	409	560	852	1,115
Net gain (loss) on fair value hedging relationships	(22)	10	(37)	24
Agency debentures [Member] \| Interest Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized as interest settlements on derivatives	(2)	0	(2)	0
Changes in fair value of hedged item	10	24	225	31
Changes in fair value of derivatives	(9)	(25)	(224)	(32)
Net gain (loss) on fair value hedging relationships	(1)	(1)	(1)	(1)
Agency mortgage-backed securities [Member] \| Interest Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized as interest settlements on derivatives	(25)	1	(37)	4
Amortization of basis adjustment	2	9	10	19
Changes in fair value of hedged item	75	414	930	688
Changes in fair value of derivatives	(73)	(413)	(939)	(686)
Net gain (loss) on fair value hedging relationships	$ (21)	$ 11	$ (36)	$ 25

Represents the amortization of basis adjustments of discontinued fair value hedges.

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Represents amounts recognized as interest settlements on fair value hedging relationships.

+ References

No definition available.

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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- Definition

Amount of gain (loss) on derivative instrument designated and qualifying as fair value hedge included in assessment of hedge effectiveness, recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 45
-Paragraph 1A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109974929&loc=SL110061172-113977

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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