Mortgage Loans Held for Sale and Investment - Reconciliation to Cash Flow (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Feb. 01, 2019
Loans Receivable Held-for-sale, Net, Reconciliation to Cash Flow [Roll Forward]
Balance - beginning of period	$ 4,077	$ 1,631
Loans sold	(13,510)	(6,088)
Mortgage loans originated and purchased, net of fees	12,375	6,253
Repurchase of loans out of Ginnie Mae securitizations	919	364
Changes in fair value	61	10
Net transfers of mortgage loans held for sale from REO in other assets and transfer from mortgage loans held for investment	0	0
Balance - end of period	$ 3,922	2,170
Pacific Union
Loans Receivable Held-for-sale, Net, Reconciliation to Cash Flow [Roll Forward]
Mortgage loans held for sale		$ 536	$ 536

Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Mortgage Loans Held For Sale

No definition available.

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- Definition

Loans Receivable Held-for-sale, Reconciliation to Cash Flow, Changes in Fair Value

+ References

No definition available.

+ Details

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- Definition

Loans Receivable Held-for-sale, Reconciliation to Cash Flow, Transfer from Held-for-sale to Held For Investment or Other Assets

+ References

No definition available.

+ Details

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- Definition

Repurchase of Ginnie Mae Receivables

+ References

No definition available.

+ Details

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- Definition

The face amount of loans that will be sold to other entities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for bad debt, of additions to loan receivables held-for-sale that are not part of a disposal group.

+ References

+ Details

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- Definition

Amount, after allowance for bad debt, of deductions to loan receivables held-for-sale that are not part of a disposal group.

+ References

+ Details

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