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:	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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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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

Represents the minimum EBITDA to debt service ratio permitted under financial covenants.

+ References

No definition available.

+ Details

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

- Definition

Represents the ratio of maximum indebtedness (excluding warehouse lines) to tangible net worth permitted under financial covenants.

+ References

No definition available.

+ Details

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

- Definition

Represents the minimum debt service coverage ratio to be maintained by the entity to comply with the financial covenants.

+ References

No definition available.

+ Details

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

- Definition

Represents the amount of minimum earnings before interest, taxes, depreciation and amortization to be maintained by the entity to comply with the financial covenants.

+ References

No definition available.

+ Details

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

- Definition

Represents the amount of minimum liquid assets to be maintained by the entity to comply with the financial covenants.

+ References

No definition available.

+ Details

Name:	wd_DebtInstrumentCovenantMinimumLiquidAssets
Namespace Prefix:	wd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the percentage of the net proceeds of any equity issuances by the entity or any of its subsidiaries, to be added to base amount of tangible net worth to calculate of minimum tangible net worth amount as per the financial covenants.

+ References

No definition available.

+ Details

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

- Definition

Represents the threshold period past due for which loans are excluded from the measurement of the entity's servicing portfolio for purposes of measuring compliance with the financial covenants of the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Represents the base amount that is used in the calculation of minimum tangible net worth amount as per the financial covenants.

+ References

No definition available.

+ Details

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

- Definition

Represents the minimum amount of aggregate unpaid principal amount of all Fannie Mae DUS mortgage loans comprising the entity's consolidated servicing portfolio.

+ References

No definition available.

+ Details

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

- Definition

Represents the minimum amount of aggregate unpaid principal amount of all mortgage loans comprising the entity's consolidated servicing portfolio under terms of debt covenant.

+ References

No definition available.

+ Details

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

- Definition

Represents the percentage of the aggregate unpaid principal balance of all Fannie Mae DUS mortgage loans as a maximum aggregate unpaid principal amount of 60 or more days past due period required to be maintained under the financial covenants.

+ References

No definition available.

+ Details

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

- Definition

Number of debt facilities.

+ References

No definition available.

+ Details

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Namespace Prefix:	wd_
Data Type:	xbrli:integerItemType
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

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

- Details

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- Details

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Debt - Covenants and Terms (Detail) $ in Millions		3 Months Ended			12 Months Ended
Debt - Covenants and Terms (Detail) $ in Millions	Dec. 21, 2015 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) facility	Dec. 31, 2014	Feb. 29, 2016 USD ($)	Feb. 16, 2016 USD ($)	Jan. 01, 2016	Mar. 31, 2015
LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit					30-day LIBOR
Agency Warehouse Facility #1
Warehouse notes payable
Maximum Amount		$ 685.0			$ 685.0			$ 425.0
Advances made as a percentage of the loan balance					100.00%
Minimum tangible net worth under covenant requirement		200.0			$ 200.0
Percentage of equity issued by the company or its subsidiaries added to base amount to determine compliance with tangible net worth covenants					75.00%
Minimum liquid asset to be maintained under financial covenants		$ 15.0			$ 15.0
Debt covenant, aggregate minimum unpaid principal amount of all mortgage loans comprising the company's consolidated servicing portfolio					20,000.0
Debt covenant, aggregate minimum unpaid principal amount of all Fannie Mae DUS mortgage loans comprising the company's consolidated servicing portfolio					$ 10,000.0
Debt covenant, exclusion from servicing portfolio measure of loans past due period					60 days
Debt covenant, maximum percentage of Fannie Mae DUS loans 60 days past due to total servicing portfolio					3.50%
Maximum indebtedness to tangible net worth					2.25
Maturity date		Oct. 31, 2016
Agency Warehouse Facility #1 \| 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		1.40%			1.40%	1.50%
Agency Warehouse Facility #1, Base
Warehouse notes payable
Maximum Amount		$ 425.0			$ 425.0
Agency Warehouse Facility #1, Base \| 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 #1, Temporary Increase
Warehouse notes payable
Maximum Amount		260.0	$ 260.0		$ 260.0
Maturity date			Feb. 16, 2016
Agency Warehouse Facility #1, Temporary Increase \| Temporary Commitment Increase Period Maturing February 16, 2016 \| LIBOR
Warehouse notes payable
Basis points added to reference rate			1.75%		1.75%
Agency Warehouse Facility #2
Warehouse notes payable
Maximum Amount		1,900.0			$ 1,900.0		$ 650.0
Advances made as a percentage of the loan balance					100.00%
Minimum tangible net worth under covenant requirement		200.0			$ 200.0
Percentage of equity issued by the company or its subsidiaries added to base amount to determine compliance with tangible net worth covenants					75.00%
Minimum liquid asset to be maintained under financial covenants		$ 15.0			$ 15.0
Debt covenant, aggregate minimum unpaid principal amount of all mortgage loans comprising the company's consolidated servicing portfolio					20,000.0
Debt covenant, aggregate minimum unpaid principal amount of all Fannie Mae DUS mortgage loans comprising the company's consolidated servicing portfolio					$ 10,000.0
Debt covenant, exclusion from servicing portfolio measure of loans past due period					60 days
Debt covenant, maximum percentage of Fannie Mae DUS loans 60 days past due to total servicing portfolio					3.50%
Maturity date					Jun. 22, 2016
Agency Warehouse Facility #2 \| 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		1.40%			1.40%	1.50%
Agency Warehouse Facility #2, Base
Warehouse notes payable
Maximum Amount		$ 650.0			$ 650.0
Agency Warehouse Facility #2, Temporary Increase
Warehouse notes payable
Maximum Amount		1,300.0			1,300.0
Agency Warehouse Facility #2, Temporary Increase \| Temporary Commitment Increase Period Maturing February 29, 2016
Warehouse notes payable
Maximum Amount		1,300.0			1,300.0
Agency Warehouse Facility #3
Warehouse notes payable
Maximum Amount		490.0		$ 240.0	$ 490.0		$ 240.0
Advances made as a percentage of the loan balance					100.00%
Minimum tangible net worth under covenant requirement		200.0			$ 200.0
Percentage of equity issued by the company or its subsidiaries added to base amount to determine compliance with tangible net worth covenants					75.00%
Minimum liquid asset to be maintained under financial covenants		15.0			$ 15.0
Debt covenant, aggregate minimum unpaid principal amount of all mortgage loans comprising the company's consolidated servicing portfolio					20,000.0
Debt covenant, aggregate minimum unpaid principal amount of all Fannie Mae DUS mortgage loans comprising the company's consolidated servicing portfolio					$ 10,000.0
Debt covenant, exclusion from servicing portfolio measure of loans past due period					60 days
Debt covenant, maximum percentage of Fannie Mae DUS loans 60 days past due to total servicing portfolio					3.50%
Maximum indebtedness to tangible net worth					2.25
Maturity date				Apr. 30, 2016
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					1.40%	1.40%
Agency Warehouse Facility #3, Base
Warehouse notes payable
Maximum Amount		240.0			$ 240.0
Agency Warehouse Facility #3, Temporary Increase
Warehouse notes payable
Maximum Amount		$ 250.0			250.0
Maturity date		Feb. 29, 2016
Agency Warehouse Facility #4
Warehouse notes payable
Maximum Amount	$ 250.0
Minimum tangible net worth under covenant requirement		$ 200.0			$ 200.0
Percentage of equity issued by the company or its subsidiaries added to base amount to determine compliance with tangible net worth covenants					75.00%
Minimum liquid asset to be maintained under financial covenants		15.0			$ 15.0
Debt covenant, aggregate minimum unpaid principal amount of all mortgage loans comprising the company's consolidated servicing portfolio					20,000.0
Debt covenant, aggregate minimum unpaid principal amount of all Fannie Mae DUS mortgage loans comprising the company's consolidated servicing portfolio					$ 10,000.0
Debt covenant, exclusion from servicing portfolio measure of loans past due period					60 days
Debt covenant, maximum percentage of Fannie Mae DUS loans 60 days past due to total servicing portfolio					3.50%
Maturity date	Dec. 20, 2016
Agency Warehouse Facility #4 \| 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	1.40%				1.40%
Uncommitted Agency Warehouse Facility
Warehouse notes payable
Maximum Amount		450.0			$ 450.0
Advances made as a percentage of the loan balance					99.00%
Uncommitted Agency Warehouse Facility \| LIBOR
Warehouse notes payable
Basis points added to reference rate					1.15%
Uncommitted Agency Warehouse Facility \| LIBOR \| Minimum
Warehouse notes payable
Basis points added to reference rate					0.35%
Interim Warehouse Facility #1
Warehouse notes payable
Maximum Amount		85.0		$ 85.0	$ 85.0
Minimum tangible net worth under covenant requirement		200.0			$ 200.0
Percentage of equity issued by the company or its subsidiaries added to base amount to determine compliance with tangible net worth covenants					75.00%
Minimum liquid asset to be maintained under financial covenants		15.0			$ 15.0
Debt covenant, aggregate minimum unpaid principal amount of all mortgage loans comprising the company's consolidated servicing portfolio					20,000.0
Debt covenant, aggregate minimum unpaid principal amount of all Fannie Mae DUS mortgage loans comprising the company's consolidated servicing portfolio					$ 10,000.0
Debt covenant, exclusion from servicing portfolio measure of loans past due period					60 days
Debt covenant, maximum percentage of Fannie Mae DUS loans 60 days past due to total servicing portfolio					3.50%
Maximum indebtedness to tangible net worth					2.25
Mimimum rolling four-quarter EBITDA to total debt service ratio					2.00
Maturity date				Apr. 30, 2016	Apr. 30, 2016
Term of debt					3 years
Interim Warehouse Facility #1 \| 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				1.90%	1.90%	2.00%
Interim Warehouse Facility #2
Warehouse notes payable
Maximum Amount		200.0		$ 200.0	$ 200.0
Minimum tangible net worth under covenant requirement		200.0			$ 200.0
Percentage of equity issued by the company or its subsidiaries added to base amount to determine compliance with tangible net worth covenants					75.00%
Minimum liquid asset to be maintained under financial covenants		15.0			$ 15.0
Debt covenant, aggregate minimum unpaid principal amount of all mortgage loans comprising the company's consolidated servicing portfolio					20,000.0
Debt covenant, aggregate minimum unpaid principal amount of all Fannie Mae DUS mortgage loans comprising the company's consolidated servicing portfolio					$ 10,000.0
Debt covenant, exclusion from servicing portfolio measure of loans past due period					60 days
Debt covenant, maximum percentage of Fannie Mae DUS loans 60 days past due to total servicing portfolio					3.50%
Minimum EBITDA to be maintained under financial covenants					$ 35.0
Debt service coverage ratio					2.75
Maturity date				Dec. 13, 2017	Dec. 13, 2017
Term of debt					3 years
Interim Warehouse Facility #2 \| 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					2.00%	2.00%
Interim Warehouse Facility #3
Warehouse notes payable
Maximum Amount		75.0			$ 75.0
Minimum tangible net worth under covenant requirement		200.0			$ 200.0
Percentage of equity issued by the company or its subsidiaries added to base amount to determine compliance with tangible net worth covenants					75.00%
Minimum liquid asset to be maintained under financial covenants		$ 15.0			$ 15.0
Maximum indebtedness to tangible net worth					3.00
Debt service coverage ratio					2.75
Maturity date					May 19, 2016
Term of debt					3 years
Interim Warehouse Facility #3 \| LIBOR
Warehouse notes payable
Reference rate for variable interest on the line of credit					30-day LIBOR	30-day LIBOR
Interim Warehouse Facility #3 \| LIBOR \| Minimum
Warehouse notes payable
Basis points added to reference rate					2.00%	2.00%
Interim Warehouse Facility #3 \| LIBOR \| Maximum
Warehouse notes payable
Basis points added to reference rate					2.50%	2.50%
CMBS
Warehouse notes payable
Percentage of ownership		40.00%		40.00%	40.00%				100.00%	20.00%
CMBS \| Master Repurchase Agreements
Warehouse notes payable
Maximum Amount		$ 200.0			$ 200.0
Number of agreements \| facility					2