All amounts that are due to the servicer of a financial asset, excluding contractually specified servicing fees and late fees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746

+ Details

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- Definition

Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- 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 interest income, net of interest paid to the borrower, on property level escrow deposits.

+ References

No definition available.

+ Details

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Namespace Prefix:	wd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Details

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- Details

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MORTGAGE SERVICING RIGHTS - Prepayment fees and Other information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Escrow earnings and other interest income
Servicing
Escrow earnings	$ 51.4	$ 38.2	$ 19.1
MSRs
Servicing
Expected amortization period for net carrying value	7 years 6 months
MSRs \| Other revenues
Servicing
Prepayment fees	$ 26.8	$ 18.9	$ 17.3