Transfers of Residential Loans - Additional Information (Detail) - USD ($) $ in Billions	6 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Transfers of Residential Loans [Line Items]
Mortgage loans sold and serviced, 60 days or more past due, percent	1.40%	1.30%
Mortgage loans sold and serviced, number of days past due threshold	60 days or more
Reverse Loans and Real Estate Owned
Transfers of Residential Loans [Line Items]
Unpaid principal balance of assets pledged as collateral to securitization pools	$ 9.4
Carrying value of assets pledged as collateral to securitization pools	$ 9.8

Carrying amount of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

This is the amount of the financial instruments that are considered delinquent (past due) at the end of the period expressed as a percent.

+ References

No definition available.

+ Details

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Namespace Prefix:	wac_
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Period Type:	instant

- Definition

The number days past due threshold for mortgage loans sold and serviced by the Company.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Unpaid principal balance of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

No definition available.

+ Details

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Namespace Prefix:	wac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Transfers of residential loans line items.

+ References

No definition available.

+ Details

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Namespace Prefix:	wac_
Data Type:	xbrli:stringItemType
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Period Type:	duration

- Details

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Namespace Prefix:
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