The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

+ 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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The funding percentage of required advances of principal and interest to be provided under this Agency Warehouse Facility sublimit.

+ References

No definition available.

+ Details

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Namespace Prefix:	wd_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of outstanding principal and interest and tax and escrow advances included as a component of other assets on the balance sheet.

+ References

No definition available.

+ Details

Name:	wd_LoansServicedAmountOfPrincipalAndInterestAndTaxEscrowAdvancesOutstanding
Namespace Prefix:	wd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The period of time that advances of principal and interest payments and guarantee fees are required to be made should a borrower cease making payments under the terms of their loan.

+ References

No definition available.

+ Details

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Namespace Prefix:	wd_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of principal and interest payment advances made on behalf of the borrower for loans serviced by the Company.

+ References

No definition available.

+ Details

Name:	wd_LoansServicedPrincipalAndInterestPaymentsAdvances
Namespace Prefix:	wd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The period with in which after serve of the notice entity has right for reimbursement of short term debt.

+ References

No definition available.

+ Details

Name:	wd_NoticePeriodForReimbursementOfShortTermDebt
Namespace Prefix:	wd_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The period of time a Ginnie Mae loan must be in default before loan can be assigned to HUD.

+ References

No definition available.

+ Details

Name:	wd_TimePeriodLoanMustBeInDefaultBeforeAssignmentToHud
Namespace Prefix:	wd_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

Name:	us-gaap_CreditFacilityAxis=wd_LineOfCreditAgencyWarehouseFacilitySublimitFannieMaeAdvancesMember
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SERVICING - (Detail) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended
SERVICING - (Detail) - USD ($) $ in Thousands	May 05, 2020	Apr. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Servicing
Total Facility Capacity			$ 4,714,184
Amount of outstanding principal and interest and tax and escrow advances included as a component of receivables, net on the balance sheet			2,600	$ 2,100
Loans serviced
Servicing
Servicing portfolio loans unpaid principal balance			94,800,000	93,200,000
Custodial escrow accounts			2,100,000	$ 2,600,000
Fannie Mae DUS Program
Servicing
Servicing portfolio loans unpaid principal balance			$ 37,200,000
Notice period of reimbursement of advances			60 days
Advances of principal and interest payments on behalf of borrowers		$ 800
Fannie Mae DUS Program \| Maximum
Servicing
Period of time advances of principal and interest payments and guarantee fees are required to be made			4 months
HUD Program
Servicing
Advances of principal and interest payments on behalf of borrowers		$ 4,500
Period of time a loan must be in default before assignment to HUD		30 days
Agency Warehouse Facility Sublimit, Fannie Mae Advances \| Fannie Mae DUS Program
Servicing
Total Facility Capacity	$ 100,000
Funding percentage of required advances of principal and interest to be provided	90.00%