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:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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/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

+ Details

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Namespace Prefix:	us-gaap_
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://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

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 CCYY-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

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

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

+ References

No definition available.

+ Details

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

WAREHOUSE NOTES PAYABLE - Schedule of Debt (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016
Warehouse notes payable
Maximum Amount		$ 3,595,000
Debt issuance costs		(1,234)
Outstanding Balance		1,406,462	$ 1,990,183
Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		3,235,000
Outstanding Balance		1,198,502
Interim Warehouse Facility
Warehouse notes payable
Maximum Amount		360,000
Outstanding Balance		$ 209,194
Agency Warehouse Facility #1 \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.40%
Agency Warehouse Facility #2 \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.40%
Agency Warehouse Facility #3 \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit	30-day LIBOR	30-day LIBOR
Basis points added to reference rate	1.25%	1.35%
Agency Warehouse Facility #3 \| Agency Warehouse Facility
Warehouse notes payable
Term of facility extension option	1 year
Maturity date	May 30, 2017
Agency Warehouse Facility #4 \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Basis points added to reference rate		1.40%
Agency Warehouse Facility #5 \| 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%
Uncommitted 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%
Interim Warehouse Facility #1 \| 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 #1 \| Interim Warehouse Facility
Warehouse notes payable
Maturity date	Apr. 30, 2018
Interim Warehouse Facility #2 \| 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 \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit		30-day LIBOR
Interim Warehouse Facility #3 \| LIBOR \| Minimum
Warehouse notes payable
Basis points added to reference rate		2.00%
Interim Warehouse Facility #3 \| LIBOR \| Maximum
Warehouse notes payable
Basis points added to reference rate		2.50%
Interim Warehouse Facility #3 \| Interim Warehouse Facility
Warehouse notes payable
Maturity date	May 19, 2018
Loans Held for Sale \| Agency Warehouse Facility #1 \| Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		$ 425,000
Outstanding Balance		130,719
Loans Held for Sale \| Agency Warehouse Facility #2 \| Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		650,000
Outstanding Balance		562,583
Loans Held for Sale \| Agency Warehouse Facility #3 \| Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		280,000
Outstanding Balance		90,358
Loans Held for Sale \| Agency Warehouse Facility #4 \| Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		350,000
Outstanding Balance		214,116
Loans Held for Sale \| Agency Warehouse Facility #5 \| Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		30,000
Outstanding Balance		20,348
Loans Held for Sale \| Uncommitted Agency Warehouse Facility \| Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		1,500,000
Outstanding Balance		180,378
Loans Held for Investment \| Interim Warehouse Facility #1 \| Interim Warehouse Facility
Warehouse notes payable
Maximum Amount		85,000
Outstanding Balance		36,916
Loans Held for Investment \| Interim Warehouse Facility #2 \| Interim Warehouse Facility
Warehouse notes payable
Maximum Amount		200,000
Outstanding Balance		113,272
Loans Held for Investment \| Interim Warehouse Facility #3 \| Interim Warehouse Facility
Warehouse notes payable
Maximum Amount		75,000
Outstanding Balance		59,006
National Banks \| Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		1,700,000
National Banks \| Interim Warehouse Facility
Warehouse notes payable
Maximum Amount		400,000
Fannie Mae \| Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		$ 1,500,000