Mortgage Servicing Rights - Components of Mortgage Servicing Rights Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Servicing income:
Income	$ 9,716	$ 3,633
Cost of sub-servicer	(1,229)rwt_MortgageServicingExpense	(316)rwt_MortgageServicingExpense
Net servicing income	8,487	3,317
Market valuation adjustments	(19,517)	(2,711)
MSR provision for repurchases	106	0
MSR income (loss)	$ (10,924)	$ 606

Mortgage Servicing Expense

No definition available.

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- Definition

Includes income from mortgage banking servicing real estate mortgages, net of subservicing costs, and market valuation changes of MSRs held at fair value.

+ References

No definition available.

+ Details

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- Definition

Provision for mortgage servicing rights repurchases.

+ References

No definition available.

+ Details

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- Definition

Total net change in market value related to mortgage servicing rights.

+ References

No definition available.

+ Details

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122596-111746

+ Details

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- Definition

The total amount of contractually specified servicing fees, late fees, and ancillary fees earned for each period for which results of operations are presented.

+ References

+ Details

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