Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

+ Details

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

- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

+ Details

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

- 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

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

Name:	wd_LineOfCreditFacilityCommittedBorrowingCapacity
Namespace Prefix:	wd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum uncommitted 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

No definition available.

+ Details

Name:	wd_LineOfCreditFacilityUncommittedBorrowingCapacity
Namespace Prefix:	wd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of financial covenants updated during the period.

+ References

No definition available.

+ Details

Name:	wd_NumberOfFinancialCovenantsUpdated
Namespace Prefix:	wd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

WAREHOUSE NOTES PAYABLE AND NOTES PAYABLE - Summary Information (Detail) $ in Thousands	1 Months Ended					9 Months Ended
	Sep. 30, 2023 USD ($)	Aug. 31, 2023	Jun. 30, 2023 item	May 31, 2023	Apr. 30, 2023	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Warehouse notes payable
Outstanding Balance	$ 790,742					$ 790,742	$ 537,531
Loans Held for Sale \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount	1,825,000					1,825,000
Uncommitted Amount	3,540,000					3,540,000
Total Facility Capacity	5,365,000					5,365,000
Outstanding Balance	765,594					765,594
National Banks \| Loans Held for Sale \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount	1,825,000					1,825,000
Uncommitted Amount	2,040,000					2,040,000
Total Facility Capacity	3,865,000					3,865,000
Outstanding Balance	552,783					552,783
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #1 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount	325,000					325,000
Uncommitted Amount	250,000					250,000
Total Facility Capacity	575,000					575,000
Outstanding Balance	92,872					$ 92,872
Maturity date		Aug. 28, 2024
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #1 \| Agency Warehouse Facility \| SOFR
Warehouse notes payable
Percentage added to reference rate						1.30%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #2 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount	700,000					$ 700,000
Uncommitted Amount	300,000					300,000
Total Facility Capacity	1,000,000					1,000,000
Outstanding Balance	133,366					$ 133,366
Maturity date					Apr. 12, 2024
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #2 \| Agency Warehouse Facility \| SOFR
Warehouse notes payable
Percentage added to reference rate						1.30%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #3 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount	600,000					$ 600,000
Uncommitted Amount	265,000					265,000
Total Facility Capacity	865,000					865,000
Outstanding Balance	106,856					$ 106,856
Maturity date				May 15, 2024
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #3 \| Agency Warehouse Facility \| SOFR
Warehouse notes payable
Percentage added to reference rate						1.35%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #4 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount	200,000					$ 200,000
Uncommitted Amount	225,000					225,000
Total Facility Capacity	425,000					425,000
Outstanding Balance	124,934					$ 124,934
Maturity date			Jun. 22, 2024
Number of financial covenants updated \| item			1
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #4 \| Agency Warehouse Facility \| SOFR \| Minimum
Warehouse notes payable
Percentage added to reference rate						1.30%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #4 \| Agency Warehouse Facility \| SOFR \| Maximum
Warehouse notes payable
Percentage added to reference rate						1.35%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #5 \| Agency Warehouse Facility
Warehouse notes payable
Uncommitted Amount	1,000,000					$ 1,000,000
Total Facility Capacity	1,000,000					1,000,000
Outstanding Balance	$ 94,755					$ 94,755
Maturity date	Sep. 12, 2024
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #5 \| Agency Warehouse Facility \| SOFR
Warehouse notes payable
Percentage added to reference rate						1.45%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility
Warehouse notes payable
Total Facility Capacity	$ 454,800					$ 454,800
Outstanding Balance	25,600					$ 25,600
National Banks \| Loans Held for Investment \| Interim Warehouse Facility \| SOFR \| Minimum
Warehouse notes payable
Percentage added to reference rate						1.35%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility \| SOFR \| Maximum
Warehouse notes payable
Percentage added to reference rate						3.25%
Fannie Mae \| Loans Held for Sale \| Fannie Mae Repurchase Agreement, Uncommitted Line and Open Maturity \| Agency Warehouse Facility
Warehouse notes payable
Uncommitted Amount	1,500,000					$ 1,500,000
Total Facility Capacity	1,500,000					1,500,000
Outstanding Balance	$ 212,811					$ 212,811