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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107314-111719

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- Definition

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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- Definition

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

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- Definition

The hypothetical financial impact of a specified adverse percentage change in 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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Mortgage Servicing Rights ("MSRs") and Related Liabilities - Fair Value Sensitivity Analysis (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Mortgage servicing rights
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Total Prepayment Speeds, 10% Adverse Change	$ (117)
Total Prepayment Speeds, 20% Adverse Change	(227)
Excess spread financing
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Total Prepayment Speeds, 10% Adverse Change	33
Total Prepayment Speeds, 20% Adverse Change	68
100 Basis Points \| Mortgage servicing rights
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Discount Rate, Adverse Change	(138)
100 Basis Points \| Excess spread financing
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Discount Rate, Adverse Change	44
200 Basis Points \| Mortgage servicing rights
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Discount Rate, Adverse Change	(266)
200 Basis Points \| Excess spread financing
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Discount Rate, Adverse Change	$ 92
Predecessor \| Mortgage servicing rights
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Total Prepayment Speeds, 10% Adverse Change		$ (118)
Total Prepayment Speeds, 20% Adverse Change		(227)
Predecessor \| Excess spread financing
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Total Prepayment Speeds, 10% Adverse Change		34
Total Prepayment Speeds, 20% Adverse Change		71
Predecessor \| 100 Basis Points \| Mortgage servicing rights
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Discount Rate, Adverse Change		(108)
Predecessor \| 100 Basis Points \| Excess spread financing
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Discount Rate, Adverse Change		37
Predecessor \| 200 Basis Points \| Mortgage servicing rights
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Discount Rate, Adverse Change		(208)
Predecessor \| 200 Basis Points \| Excess spread financing
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Discount Rate, Adverse Change		$ 78