Loans Held-for-Investment - Summary of TDRs by Type and Performing Status (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Troubled Debt Restructurings
TDR balance	$ 37	$ 46
Financing receivable, modifications, loans and leases receivable, allowance	4	5
TDR loans under fair value option	5	3
Consumer loans
Troubled Debt Restructurings
TDR balance	35	41
Consumer loans \| Residential first mortgage
Troubled Debt Restructurings
TDR balance	25	27
Consumer loans \| Home equity
Troubled Debt Restructurings
TDR balance	10	14
Commercial Loans
Troubled Debt Restructurings
TDR balance	2	5
Commercial Loans \| Commercial real estate
Troubled Debt Restructurings
TDR balance		5
Commercial Loans \| Commercial and industrial
Troubled Debt Restructurings
TDR balance	2
Performing
Troubled Debt Restructurings
TDR balance	24	36
Performing \| Consumer loans
Troubled Debt Restructurings
TDR balance	22	31
Performing \| Consumer loans \| Residential first mortgage
Troubled Debt Restructurings
TDR balance	14	19
Performing \| Consumer loans \| Home equity
Troubled Debt Restructurings
TDR balance	8	12
Performing \| Commercial Loans
Troubled Debt Restructurings
TDR balance	2	5
Performing \| Commercial Loans \| Commercial real estate
Troubled Debt Restructurings
TDR balance		5
Performing \| Commercial Loans \| Commercial and industrial
Troubled Debt Restructurings
TDR balance	2
Nonperforming
Troubled Debt Restructurings
TDR balance	13	10
Nonperforming \| Consumer loans
Troubled Debt Restructurings
TDR balance	13	10
Nonperforming \| Consumer loans \| Residential first mortgage
Troubled Debt Restructurings
TDR balance	11	8
Nonperforming \| Consumer loans \| Home equity
Troubled Debt Restructurings
TDR balance	2	2
Nonperforming \| Commercial Loans
Troubled Debt Restructurings
TDR balance	0	0
Nonperforming \| Commercial Loans \| Commercial real estate
Troubled Debt Restructurings
TDR balance		$ 0
Nonperforming \| Commercial Loans \| Commercial and industrial
Troubled Debt Restructurings
TDR balance	$ 0

The TDR loans held-for-investment carried under the fair value option method.

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- Definition

Financing Receivable, Modifications, Loans and Leases Receivable, Allowance

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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-Section 50
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