Name:	coop_AssumptionForFairValueOfAssetsOrLiabilitiesThatRelateToTransferorsContinuingInvolvementAdvancedFinancingAndCounterpartyFeeRates
Namespace Prefix:	coop_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	duration

Assumption For Fair Value Of Assets Or Liabilities That Relate To Transferors Continuing Involvement, Cost to Service Per Loan

No definition available.

Name:	coop_AssumptionForFairValueOfAssetsOrLiabilitiesThatRelateToTransferorsContinuingInvolvementCostToServicePerLoan
Namespace Prefix:	coop_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Assumption For Fair Value Of Assets Or Liabilities That Relate To Transferors Continuing Involvement, Market Pricing

No definition available.

Name:	coop_AssumptionForFairValueOfAssetsOrLiabilitiesThatRelateToTransferorsContinuingInvolvementMarketPricing
Namespace Prefix:	coop_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Option Adjusted Spread

No definition available.

Name:	coop_AssumptionForFairValueOfAssetsOrLiabilitiesThatRelateToTransferorsContinuingInvolvementOptionAdjustedSpread
Namespace Prefix:	coop_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Value of Servicing

No definition available.

Name:	coop_AssumptionForFairValueOfAssetsOrLiabilitiesThatRelateToTransferorsContinuingInvolvementValueOfServicing
Namespace Prefix:	coop_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Annual Advanced Recovery Rates

No definition available.

Name:	coop_AssumptionforFairValueofAssetsorLiabilitiesthatrelatetoTransferorsContinuingInvolvementAnnualAdvancedRecoveryRates
Namespace Prefix:	coop_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	duration

Weighted average life of securitized assets regardless of when the transfer occurred, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4

Name:	us-gaap_AssumptionForFairValueOfAssetsOrLiabilitiesThatRelateToTransferorsContinuingInvolvementWeightedAverageLife1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

Name:	us-gaap_AssumptionForFairValueOfInterestsContinuedToBeHeldByTransferorServicingAssetsOrLiabilitiesPrepaymentSpeed
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

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.

No definition available.

Name:	us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	us-gaap_FinancialInstrumentAxis=coop_ForwardMSRMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=coop_ExcessSpreadFinancingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=coop_MortgageLoansHeldForSaleMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_InterestRateLockCommitmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=coop_MSRFinancingLiabilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: