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

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- 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/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ 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 CCYY-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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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

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

- Definition

The period of time for a line of credit extension option.

+ References

No definition available.

+ Details

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

- Definition

Represents the advance under the credit facility as a percentage of loans made by the reporting entity.

+ References

No definition available.

+ Details

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Data Type:	num: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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the uncommitted borrowing capacity feature of the credit facility terminates, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Details

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WAREHOUSE NOTES PAYABLE - Summary Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Warehouse notes payable
Committed Amount		$ 2,545,000
Uncommitted Amount		2,450,000
Total Facility Capacity		4,995,000
Outstanding Balance		802,496	$ 937,769
Debt issuance costs		$ (1,705)
Agency Warehouse Facility #1 \| Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.30%
Agency Warehouse Facility #2 \| Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.30%
Agency Warehouse Facility #3 \| Agency Warehouse Facility
Warehouse notes payable
Uncommitted Amount	$ 265,000
Total Facility Capacity	$ 500,000
Maturity date	Apr. 30, 2019
Expiration date of the uncommitted borrowing capacity	Jan. 30, 2019
Agency Warehouse Facility #3 \| Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.25%
Agency Warehouse Facility #4 \| Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.30%
Agency Warehouse Facility #5 \| Agency Warehouse Facility
Warehouse notes payable
Term of facility extension option		1 year
Maturity date		Jul. 12, 2019
Agency Warehouse Facility #5 \| Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.80%
Agency Warehouse Facility #6 \| Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.35%
Agency Warehouse Facility #7 \| Agency Warehouse Facility
Warehouse notes payable
Maturity date		Feb. 02, 2019
Advances made as a percentage of the loan balance		100.00%
Agency Warehouse Facility #7 \| Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.30%
Interim Warehouse Facility #1 \| Interim Warehouse Facility
Warehouse notes payable
Maturity date	Apr. 30, 2019
Interim Warehouse Facility #1 \| Interim Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.90%
Interim Warehouse Facility #2 \| Interim Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		2.00%
Interim Warehouse Facility #3 \| Interim Warehouse Facility
Warehouse notes payable
Maturity date	May 19, 2019
Interim Warehouse Facility #3 \| Interim Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Interim Warehouse Facility #3 \| Interim Warehouse Facility \| LIBOR \| Minimum
Warehouse notes payable
Basis points added to reference rate		2.00%
Interim Warehouse Facility #3 \| Interim Warehouse Facility \| LIBOR \| Maximum
Warehouse notes payable
Basis points added to reference rate		2.50%
Loans Held for Sale \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		$ 2,285,000
Uncommitted Amount		2,450,000
Total Facility Capacity		4,735,000
Outstanding Balance		769,249
Loans Held for Sale \| Agency Warehouse Facility #1 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		425,000
Uncommitted Amount		300,000
Total Facility Capacity		725,000
Outstanding Balance		120,903
Loans Held for Sale \| Agency Warehouse Facility #2 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		500,000
Uncommitted Amount		300,000
Total Facility Capacity		800,000
Outstanding Balance		177,577
Loans Held for Sale \| Agency Warehouse Facility #3 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		480,000
Total Facility Capacity		480,000
Outstanding Balance		102,541
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		228,680
Loans Held for Sale \| Agency Warehouse Facility #5 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		30,000
Total Facility Capacity		30,000
Outstanding Balance		19,017
Loans Held for Sale \| Agency Warehouse Facility #6 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		250,000
Uncommitted Amount		250,000
Total Facility Capacity		500,000
Loans Held for Sale \| Agency Warehouse Facility #7 \| Agency Warehouse Facility
Warehouse notes payable
Committed Amount		250,000
Uncommitted Amount		100,000
Total Facility Capacity		350,000
Outstanding Balance		63,547
Loans Held for Investment \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		260,000
Total Facility Capacity		260,000
Outstanding Balance		34,952
Loans Held for Investment \| Interim Warehouse Facility #1 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		85,000
Total Facility Capacity		85,000
Outstanding Balance		10,290
Loans Held for Investment \| Interim Warehouse Facility #2 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		100,000
Total Facility Capacity		100,000
Outstanding Balance		24,662
Loans Held for Investment \| Interim Warehouse Facility #3 \| Interim Warehouse Facility
Warehouse notes payable
Committed Amount		75,000
Total Facility Capacity		75,000
National Banks \| Agency Warehouse Facility
Warehouse notes payable
Total Facility Capacity		3,200,000
National Banks \| Interim Warehouse Facility
Warehouse notes payable
Total Facility Capacity		$ 300,000
Fannie Mae \| Uncommitted Agency Warehouse Facility \| Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.15%
Fannie Mae \| Loans Held for Sale \| Uncommitted Agency Warehouse Facility \| Agency Warehouse Facility
Warehouse notes payable
Uncommitted Amount		$ 1,500,000
Total Facility Capacity		1,500,000
Outstanding Balance		$ 56,984