Mortgage Servicing Rights - Summary of Adverse Changes to Weighted-Average Assumptions on the Fair Value of Servicing Rights (Details) - Mortgage Servicing Rights $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($)
Actual
Option adjusted spread	5.90%
Constant prepayment rate	7.90%
Weighted average cost to service per loan	$ 68
Fair value impact due to 10% adverse change
Option adjusted spread	1,012
Constant prepayment rate	1,000
Weighted average cost to service per loan	1,023
Fair value impact due to 20% adverse change
Option adjusted spread	992
Constant prepayment rate	970
Weighted average cost to service per loan	$ 1,013

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Sensitivity analysis adverse change tranche 1.

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Sensitivity analysis, adverse change, tranche 2.

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The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719

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The hypothetical financial impact of a 10 percent adverse change of the specified assumption on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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The hypothetical financial impact of a 10 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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The hypothetical financial impact of a 20 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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The hypothetical financial impact of a 20 percent adverse change of the specified assumption on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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The hypothetical financial impact of a 20 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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A specified percentage variance in the discount rate assumption in the determination of fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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The hypothetical financial impact of a specified adverse percentage change in a specified other assumption on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities).

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A specified percentage variance in the prepayment speed assumption in the determination of fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities).

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