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

No definition available.

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

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
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Balance Type:	debit
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
-Publisher FASB
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-Topic 210
-SubTopic 10
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+ Details

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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

+ Details

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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

No definition available.

+ Details

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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

The interest rate percentage floor when determining variable rate options under the terms of a debt agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	wd_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- 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

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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

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

- Definition

Number of credit facilities.

+ References

No definition available.

+ Details

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

WAREHOUSE NOTES PAYABLE - Summary Information (Detail) $ in Thousands	3 Months Ended
	Jun. 30, 2022	Mar. 31, 2022 USD ($) facility	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Warehouse notes payable
Committed Amount		$ 2,709,810
Uncommitted Amount		3,115,000
Total Facility Capacity		5,824,810
Outstanding Balance		924,280		$ 1,941,572
Debt issuance costs		(422)
Alliant Warehouse Facility
Warehouse notes payable
Committed Amount		30,000
Total Facility Capacity		30,000
Outstanding Balance		$ 12,005
Maturity date	Jul. 31, 2022
Alliant Warehouse Facility \| Adjusted Term SOFR
Warehouse notes payable
Percentage added to reference rate	3.00%
Alliant Warehouse Facility \| Adjusted Term SOFR \| Minimum
Warehouse notes payable
Interest rate floor	1.50%
Alliant Warehouse Facility \| Daily LIBOR
Warehouse notes payable
Percentage added to reference rate		3.00%
Loans Held for Sale
Warehouse notes payable
Interest expense		$ 5,333	$ 6,659
Loans Held for Sale \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		2,225,000
Uncommitted Amount		3,115,000
Total Facility Capacity		5,340,000
Outstanding Balance		751,078
Loans Held for Investment
Warehouse notes payable
Interest expense		1,107	$ 1,132
National Banks \| Agency Warehouse Facility
Warehouse notes payable
Total Facility Capacity		3,800,000
National Banks \| Interim Warehouse Facility
Warehouse notes payable
Total Facility Capacity		$ 500,000
National Banks \| Loans Held for Sale \| Agency Warehouse Facility
Warehouse notes payable
Number of credit facilities \| facility		6
Committed Amount		$ 2,225,000
Uncommitted Amount		1,615,000
Total Facility Capacity		3,840,000
Outstanding Balance		659,748
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #1 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		425,000
Total Facility Capacity		425,000
Outstanding Balance		$ 49,860
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #1 \| Agency Warehouse Facility \| Adjusted Term 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
Uncommitted Amount		300,000
Total Facility Capacity		1,000,000
Outstanding Balance		$ 46,647
Maturity date	Apr. 13, 2023
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #2 \| Agency Warehouse Facility \| 30-day LIBOR
Warehouse notes payable
Percentage added to reference rate		1.30%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #2 \| Agency Warehouse Facility \| Adjusted Term 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
Uncommitted Amount		265,000
Total Facility Capacity		865,000
Outstanding Balance		$ 274,690
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #3 \| Agency Warehouse Facility \| 30-day LIBOR
Warehouse notes payable
Percentage added to reference rate		1.30%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #4 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		$ 350,000
Total Facility Capacity		350,000
Outstanding Balance		$ 128,298
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #4 \| Agency Warehouse Facility \| 30-day LIBOR
Warehouse notes payable
Percentage added to reference rate		1.30%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #5 \| Agency Warehouse Facility
Warehouse notes payable
Uncommitted Amount		$ 1,000,000
Total Facility Capacity		1,000,000
Outstanding Balance		$ 135,453
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #5 \| Agency Warehouse Facility \| Adjusted Term SOFR
Warehouse notes payable
Percentage added to reference rate		1.45%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #6 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		$ 150,000
Uncommitted Amount		50,000
Total Facility Capacity		200,000
Outstanding Balance		$ 24,800
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #6 \| Agency Warehouse Facility \| 30-day LIBOR
Warehouse notes payable
Percentage added to reference rate		1.30%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility, Expired \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		$ 150,000
National Banks \| Loans Held for Investment \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		454,810
Total Facility Capacity		454,810
Outstanding Balance		161,619
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #1 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		135,000
Total Facility Capacity		$ 135,000
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #1 \| Interim Warehouse Facility \| 30-day LIBOR
Warehouse notes payable
Percentage added to reference rate		1.90%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #2 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		$ 100,000
Total Facility Capacity		$ 100,000
Maturity date		Dec. 13, 2023
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #2 \| Interim Warehouse Facility \| Adjusted Term SOFR \| Minimum
Warehouse notes payable
Percentage added to reference rate		1.35%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #2 \| Interim Warehouse Facility \| Adjusted Term SOFR \| Maximum
Warehouse notes payable
Percentage added to reference rate		1.85%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #3 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		$ 200,000
Total Facility Capacity		200,000
Outstanding Balance		$ 141,809
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #3 \| Interim Warehouse Facility \| 30-day LIBOR \| Minimum
Warehouse notes payable
Percentage added to reference rate		1.75%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #3 \| Interim Warehouse Facility \| 30-day LIBOR \| Maximum
Warehouse notes payable
Percentage added to reference rate		3.25%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #4 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		$ 19,810
Total Facility Capacity		19,810
Outstanding Balance		$ 19,810
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #4 \| Interim Warehouse Facility \| 30-day LIBOR
Warehouse notes payable
Percentage added to reference rate		3.00%
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
Total Facility Capacity		1,500,000
Outstanding Balance		$ 91,330