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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

+ Details

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

- 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
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: 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(16))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

+ 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

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

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

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

WAREHOUSE NOTES PAYABLE - Summary Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended				9 Months Ended
	Oct. 31, 2022	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Warehouse notes payable
Committed Amount			$ 2,309,810			$ 2,309,810
Uncommitted Amount			3,540,000			3,540,000
Total Facility Capacity			5,849,810			5,849,810
Outstanding Balance			2,545,406			2,545,406	$ 1,941,572
Debt issuance costs			(892)			(892)
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			2,357,720			2,357,720
National Banks \| Agency Warehouse Facility
Warehouse notes payable
Total Facility Capacity			3,900,000			3,900,000
National Banks \| Interim Warehouse Facility
Warehouse notes payable
Total Facility Capacity			500,000			500,000
National Banks \| Tax Credit Equity Warehouse Facility
Warehouse notes payable
Committed Amount			30,000			30,000
Total Facility Capacity			30,000			30,000
Outstanding Balance			$ 5,300			$ 5,300
Maturity date			Oct. 14, 2022
National Banks \| Tax Credit Equity Warehouse Facility \| Adjusted Term SOFR
Warehouse notes payable
Percentage added to reference rate			3.00%			3.00%
National Banks \| Tax Credit Equity Warehouse Facility \| Adjusted Term SOFR \| Minimum
Warehouse notes payable
Interest rate floor			1.50%
National Banks \| Tax Credit Equity Warehouse Facility \| Daily LIBOR
Warehouse notes payable
Percentage added to reference rate				3.00%
National Banks \| New Warehouse Facility
Warehouse notes payable
Maturity date	Oct. 05, 2025
National Banks \| New Warehouse Facility \| Maximum
Warehouse notes payable
Committed Amount	$ 20,000
National Banks \| New Warehouse Facility \| Adjusted Term SOFR
Warehouse notes payable
Percentage added to reference rate	2.80%
National Banks \| New Warehouse Facility \| Adjusted Term SOFR \| Minimum
Warehouse notes payable
Interest rate floor	0.00%
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			1,850,308			1,850,308
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #1 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount			325,000	$ 425,000		325,000
Uncommitted Amount			250,000			250,000
Total Facility Capacity			575,000			575,000
Outstanding Balance			$ 147,070			$ 147,070
Maturity date			Aug. 30, 2023
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			$ 700,000
Uncommitted Amount			300,000			300,000
Total Facility Capacity			1,000,000			1,000,000
Outstanding Balance			536,956			$ 536,956
Maturity date				Apr. 13, 2023
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%		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			420,585			$ 420,585
Maturity date				May 15, 2023
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #3 \| Agency Warehouse Facility \| Adjusted Term SOFR
Warehouse notes payable
Percentage added to reference rate				1.35%		1.35%
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #3 \| Agency Warehouse Facility \| Adjusted Term SOFR \| Minimum
Warehouse notes payable
Interest rate floor				0.15%
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	$ 350,000	425,000
Outstanding Balance			92,924			$ 92,924
Maturity date				Jun. 22, 2023
National Banks \| Loans Held for Sale \| Agency Warehouse Facility #4 \| Agency Warehouse Facility \| Adjusted Term SOFR
Warehouse notes payable
Percentage added to reference rate				1.30%		1.30%
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			$ 652,773			$ 652,773
Maturity date			Sep. 14, 2023
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 Investment \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount			$ 454,810			$ 454,810
Total Facility Capacity			454,810			454,810
Outstanding Balance			183,278			183,278
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #1 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount			135,000			135,000
Total Facility Capacity			135,000			$ 135,000
Maturity date				May 15, 2023
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #1 \| Interim Warehouse Facility \| Adjusted Term SOFR
Warehouse notes payable
Percentage added to reference rate				1.80%		1.80%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #2 \| Adjusted Term SOFR \| Minimum
Warehouse notes payable
Percentage added to reference rate					1.35%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #2 \| Adjusted Term SOFR \| Maximum
Warehouse notes payable
Percentage added to reference rate					1.85%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #2 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount			100,000			$ 100,000
Total Facility Capacity			100,000			$ 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			$ 200,000
Total Facility Capacity			200,000			200,000
Outstanding Balance			$ 163,468			$ 163,468
Maturity date			Sep. 29, 2023
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			$ 19,810
Total Facility Capacity			19,810			19,810
Outstanding Balance			19,810			$ 19,810
Maturity date		Oct. 01, 2024
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%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #4 \| Interim Warehouse Facility \| Adjusted Term SOFR
Warehouse notes payable
Percentage added to reference rate		3.11%
National Banks \| Loans Held for Investment \| Interim Warehouse Facility #4 \| Interim Warehouse Facility \| Adjusted Term SOFR \| Minimum
Warehouse notes payable
Interest rate floor		0.15%
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			$ 507,412			$ 507,412