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Business Combination, Common Stock, Right To Receive In Shares

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Payment For Conversion Fee Of Convertible Debt

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Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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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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In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Face amount or stated value per share of common stock.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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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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Acquisitions - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	Aug. 01, 2018	Jul. 13, 2018	Feb. 12, 2018	Sep. 30, 2018	Jul. 31, 2018	Jul. 12, 2018
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)				$ 0.01
WMIH Corp And Wand Merger Corporation
Business Acquisition [Line Items]
Right to receive in cash (in dollars per share)			$ 18.00
Right to receive in shares (shares)			12.7793
Common stock, par value (in dollars per share)			$ 0.00001
Cash consideration			$ 1,226
Acquisition costs						$ 92
Debt issuance costs						38
Nationstar Mortgage Holdings Inc.
Business Acquisition [Line Items]
Cash consideration	$ 1,226
Estimated consideration	1,777
Stock consideration	551
Bargain purchase amount	2
Intangible assets acquired	103
Nationstar Mortgage Holdings Inc.
Business Acquisition [Line Items]
Acquisition costs				$ 7	$ 27
Xome Holdings LLC \| Assurant Mortgage Solutions Group
Business Acquisition [Line Items]
Cash consideration	35
Intangible assets acquired	23
Goodwill acquired	$ 3
8.125% Due July 2023
Business Acquisition [Line Items]
Debt issued		$ 950
Interest rate		8.125%
9.125% Due July 2026
Business Acquisition [Line Items]
Debt issued		$ 750
Interest rate		9.125%
KKR Capital Markets LLC \| WMIH Corp And Wand Merger Corporation
Business Acquisition [Line Items]
Acquisition costs						25
KCM \| WMIH Corp And Wand Merger Corporation
Business Acquisition [Line Items]
Acquisition costs						$ 7
Payment for conversion fee		$ 8