Mortgage Servicing Rights ("MSRs") and Related Liabilities - Servicing Revenue (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Mortgage Servicing Rights [Line Items]
Contractually specified servicing fees	$ 281
Other service-related income	9
Incentive and modification income	7
Late fees	25
Reverse servicing fees	50
Mark-to-market adjustments	(23)
Counterparty revenue share	(293)
Amortization, net of accretion	(48)
Total servicing revenue	$ 8
Predecessor
Mortgage Servicing Rights [Line Items]
Contractually specified servicing fees		$ 250
Other service-related income		19
Incentive and modification income		15
Late fees		24
Reverse servicing fees		28
Mark-to-market adjustments		(48)
Counterparty revenue share		152
Amortization, net of accretion		(45)
Total servicing revenue		$ 395

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746

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