Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
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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.

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Other Assets - Changes in the Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	3 Months Ended	5 Months Ended	7 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Jul. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Balance - end of period		$ 23		$ 120	$ 23
Pacific Union Financial, LLC
Goodwill [Roll Forward]
Addition from acquisitions				40
Seterus Mortgage Servicing Platform And Related IBM Assets
Goodwill [Roll Forward]
Addition from acquisitions				2
Nationstar Mortgage Holdings Inc.
Goodwill [Roll Forward]
Addition from acquisitions					10
Measurement period adjustment related to merger	$ 55			55
Balance - end of period		10		65	10
WMIH Corp
Goodwill [Roll Forward]
Addition from acquisitions		13		42
Measurement period adjustment related to merger		0		55
Balance - end of period		$ 23	$ 10	$ 120	$ 23
Nationstar Mortgage Holdings Inc.
Goodwill [Roll Forward]
Addition from acquisitions			0
Measurement period adjustment related to merger			0
Balance - end of period			$ 72