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

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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Amount of financing receivable modified as troubled debt restructuring.

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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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-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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Loans Held-for-Investment - Summary of TDRs by Type and Performing Status and Newly Modified TDRs (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022 USD ($) loan	Mar. 31, 2021 USD ($) loan	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Troubled Debt Restructurings
TDRs	$ 35		$ 37
Allowance for loan losses	131	$ 241	154	$ 252
TDR loans under fair value option	$ 3		5
Number of Accounts (in loans) \| loan	10	6
Pre-Modification Unpaid Principal Balance	$ 2	$ 3
Post-Modification Unpaid Principal Balance	2	$ 3
Troubled debt restructurings
Troubled Debt Restructurings
Allowance for loan losses	4		4
Performing
Troubled Debt Restructurings
TDRs	23		24
Nonperforming
Troubled Debt Restructurings
TDRs	$ 12		13
Residential first mortgage loans
Troubled Debt Restructurings
Number of Accounts (in loans) \| loan	9	6
Pre-Modification Unpaid Principal Balance	$ 2	$ 3
Post-Modification Unpaid Principal Balance	$ 2	3
Home equity
Troubled Debt Restructurings
Number of Accounts (in loans) \| loan	1
Pre-Modification Unpaid Principal Balance	$ 0
Post-Modification Unpaid Principal Balance	$ 0
Commercial real estate
Troubled Debt Restructurings
Number of Accounts (in loans) \| loan	0
Pre-Modification Unpaid Principal Balance	$ 0
Post-Modification Unpaid Principal Balance	0
Consumer loans
Troubled Debt Restructurings
TDRs			35
Consumer loans \| Performing
Troubled Debt Restructurings
TDRs			22
Consumer loans \| Nonperforming
Troubled Debt Restructurings
TDRs			13
Consumer loans \| Residential first mortgage loans
Troubled Debt Restructurings
TDRs	26		25
Allowance for loan losses	43	45	40	49
Consumer loans \| Residential first mortgage loans \| Performing
Troubled Debt Restructurings
TDRs	16		14
Consumer loans \| Residential first mortgage loans \| Nonperforming
Troubled Debt Restructurings
TDRs	10		11
Consumer loans \| Home equity
Troubled Debt Restructurings
TDRs	9		10
Allowance for loan losses	16	20	14	25
Consumer loans \| Home equity \| Performing
Troubled Debt Restructurings
TDRs	7		8
Consumer loans \| Home equity \| Nonperforming
Troubled Debt Restructurings
TDRs	2		2
Commercial loans
Troubled Debt Restructurings
TDRs			2
Commercial loans \| Performing
Troubled Debt Restructurings
TDRs			2
Commercial loans \| Nonperforming
Troubled Debt Restructurings
TDRs			0
Commercial loans \| Commercial and industrial
Troubled Debt Restructurings
TDRs			2
Allowance for loan losses	$ 13	$ 55	32	$ 51
Commercial loans \| Commercial and industrial \| Performing
Troubled Debt Restructurings
TDRs			2
Commercial loans \| Commercial and industrial \| Nonperforming
Troubled Debt Restructurings
TDRs			$ 0