Loans and Leases - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
LGG loans	$ 700
LGG loans, repurchase liability	300
LGG loans, repossessed assets	13
Loans held for sale, at fair value	1,305		$ 1,115
Loans reclassified to held-for-sale	360
Loans 90 days or greater past due and still accruing	13		0
Residential mortgage loans in process of foreclosure	122		122
Loans modified	46	$ 47
Mortgage Loans: \| One-to-four family first mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans 90 days or greater past due and still accruing	0		$ 0
Loans modified that subsequently defaulted	1
Loans modified	$ 2

Financing Receivable, Excluding, Accrued Interest, Modified Period

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- Definition

Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default

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No definition available.

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- Definition

Financing Receivable, With Government Guaranty

+ References

No definition available.

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- Definition

Financing Receivable, With Government Guaranty, Repurchase Liability

+ References

No definition available.

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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.

+ References

No definition available.

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Amortized cost excluding accrued interest, of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (c)
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- Definition

Amount of financing receivable reclassified to held-for-sale.

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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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