Real Estate Owned Loans, Government Guarantee

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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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.

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Amount of loss from the write-down 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.

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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.

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Other Assets - Narrative (Details) - USD ($)		5 Months Ended	7 Months Ended	12 Months Ended
Other Assets - Narrative (Details) - USD ($)	Aug. 01, 2018	Dec. 31, 2018	Jul. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Indefinite-lived Intangible Assets [Line Items]
Addition from acquisitions		$ 13,000,000
Goodwill impairment charge		0	$ 0		$ 0	$ 0
Amortization expense		23,000,000	2,000,000		5,000,000	$ 8,000,000
Real estate owned loans with government or GSE guarantee		10,000,000		$ 10,000,000	$ 15,000,000
Nationstar Mortgage Holdings Inc.
Indefinite-lived Intangible Assets [Line Items]
Intangible assets acquired	$ 103,000,000		$ 0
Xome Holdings LLC \| Assurant Mortgage Solutions Group
Indefinite-lived Intangible Assets [Line Items]
Intangible assets acquired		$ 24,000,000		24,000,000
Addition from acquisitions	$ 3,000,000			$ 0