Debt Instrument, Call Date, Weighted Average Term

No definition available.

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- Definition

Debt Instrument, Debt Redemption, Amount Of Principal Redeemed

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Debt Instrument, Principal Amount Outstanding

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum percentage redeemable of aggregate principal on unsecured debt with the net proceeds of certain equity offerings at a fixed redemption prices, plus accrued and unpaid interest and additional interest, if any, to the redemption dates, subject to compliance with certain conditions.

+ References

No definition available.

+ Details

Name:	nsm_MaximumPercentageRedeemableofAggregatePrincipalonUnsecuredDebt
Namespace Prefix:	nsm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Payment for Repurchase of Unsecured Debt

+ References

No definition available.

+ Details

Name:	nsm_PaymentforRepurchaseofUnsecuredDebt
Namespace Prefix:	nsm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property.

+ References

No definition available.

+ Details

Name:	us-gaap_NonRecourseDebt
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This is the principal amount outstanding for securitized loans only (across all types of loans).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=d3e107314-111719

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Indebtedness - Narrative (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
Indebtedness - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2018	Jul. 31, 2018	Dec. 31, 2019	Dec. 31, 2017	Nov. 30, 2009
Debt Instrument [Line Items]
Repurchase of unsecured senior notes	$ 1,030	$ 62	$ 100	$ 123
Maximum percentage redeemable on secured debt			35.00%
Principal amount outstanding on securitized financing					$ 222
Non-recourse debt	6,795		$ 5,286
Legacy Asset
Debt Instrument [Line Items]
Non-recourse debt	29		$ 0
Other Nonrecourse Debt
Debt Instrument [Line Items]
Unpaid principal outstanding on securitized financing	29
Non-recourse debt	29
New Notes
Debt Instrument [Line Items]
Maximum percentage redeemable on secured debt			40.00%
Unsecured Senior Notes
Debt Instrument [Line Items]
Amount of principal redeemed	658		$ 100
Repayment of debt	364
Repurchase of unsecured senior notes		60
Loss on repurchase of debt		$ 2
Secured Debt \| Legacy Asset
Debt Instrument [Line Items]
Interest rate					7.50%
Securities Pledged as Collateral
Debt Instrument [Line Items]
Principal amount outstanding on securitized financing	$ 160
Minimum \| Other Nonrecourse Debt
Debt Instrument [Line Items]
Interest rate			1.90%
Minimum \| Secured Debt \| HECM Securitizations
Debt Instrument [Line Items]
Interest rate			2.30%
Weighted average useful life			1 year
Maximum \| Other Nonrecourse Debt
Debt Instrument [Line Items]
Interest rate			5.70%
Maximum \| Secured Debt \| HECM Securitizations
Debt Instrument [Line Items]
Interest rate			6.00%
Weighted average useful life			3 years