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

No definition available.

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Data Type:	num:percentItemType
Balance Type:	na
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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

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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

- 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

Date when the debt instrument is scheduled to be fully repaid, 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

Amount of the required periodic payments including both interest and principal payments.

+ 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 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Asset coverage ratio.

+ References

No definition available.

+ Details

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

- Definition

Debt discount percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	wd_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum interest rate if an event of default has occurred as defined under the terms debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	wd_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of required mandatory prepayment under terms of the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	wd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum amount of all incremental term loans.

+ References

No definition available.

+ Details

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

- Definition

Interest coverage ratio.

+ References

No definition available.

+ Details

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

- Definition

Number of additional term loans.

+ References

No definition available.

+ Details

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

- Details

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DEBT - Notes Payable - Terms (Detail) $ in Millions		1 Months Ended	3 Months Ended		12 Months Ended
DEBT - Notes Payable - Terms (Detail) $ in Millions	Dec. 20, 2013 USD ($) loan	Apr. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015	Dec. 31, 2014
LIBOR
Debt
Reference rate					30-day LIBOR	30-day LIBOR
Term Loan Agreement
Debt
Amount of loan agreement	$ 175.0
Maximum amount of all incremental term loans	$ 60.0
Discount on issue of term loan (as a percent)	1.00%
Quarterly equal installments			$ 0.3	$ 0.4	$ 0.3
Mandatory prepayment		$ 3.6
Debt instrument maturity date					Dec. 20, 2020
Minimum LIBOR rate, default terms (as a percent)					1.00%
Term Loan Agreement \| Prime rate (Base)
Debt
Reference rate					prime rate
Term Loan Agreement \| Federal funds rate (Base)
Debt
Reference rate					Federal funds rate
Basis points added to reference rate					0.50%
Term Loan Agreement \| 30-day LIBOR (Base)
Debt
Reference rate					one month LIBOR
Basis points added to reference rate					1.00%
Term Loan Agreement \| Base Rate Loans, Leverage Ratio >2.50
Debt
Basis points added to reference rate					3.50%
Term Loan Agreement \| Base Rate Loans, Leverage Ratio less than or equal to 2.50
Debt
Basis points added to reference rate					3.25%
Term Loan Agreement \| LIBOR, Leverage Ratio >2.50
Debt
Basis points added to reference rate					4.50%
Term Loan Agreement \| LIBOR, Leverage Ratio less than or equal to 2.50
Debt
Basis points added to reference rate					4.25%
Term Loan Agreement \| January 1, 2015 through December 31, 2015 \| Base Rate
Debt
Basis points added to reference rate					3.25%
Term Loan Agreement \| January 1, 2015 through December 31, 2015 \| LIBOR
Debt
Basis points added to reference rate					4.25%
Minimum \| Term Loan Agreement
Debt
Consolidated Corporate Interest Coverage Ratio					2.75
Asset Coverage Ratio					1.50
Minimum \| Term Loan Agreement \| Base Rate Loans, Leverage Ratio >2.50
Debt
Consolidated Corporate Leverage Ratio					2.50
Minimum \| Term Loan Agreement \| LIBOR, Leverage Ratio >2.50
Debt
Consolidated Corporate Leverage Ratio					2.50
Maximum
Debt
Consolidated Corporate Leverage Ratio							2.50
Maximum \| Closing Date through December 31, 2014
Debt
Consolidated Corporate Leverage Ratio					5.00
Maximum \| January 1, 2015 through December 31, 2015
Debt
Consolidated Corporate Leverage Ratio					4.75
Maximum \| January 1, 2016 through December 31, 2016
Debt
Consolidated Corporate Leverage Ratio					4.50
Maximum \| January 1, 2017 and thereafter
Debt
Consolidated Corporate Leverage Ratio					4.25
Maximum \| Term Loan Agreement
Debt
Number of additional term loans \| loan	3
Maximum \| Term Loan Agreement \| Base Rate Loans, Leverage Ratio less than or equal to 2.50
Debt
Consolidated Corporate Leverage Ratio					2.50
Maximum \| Term Loan Agreement \| LIBOR, Leverage Ratio less than or equal to 2.50
Debt
Consolidated Corporate Leverage Ratio					2.50