Number Of Available for Sale Securities

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- Definition

Number of Securities, Continuous Unrealized Loss Position More Than Twelve Months

+ References

No definition available.

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- Definition

The aggregate net change in market value for certain assets and liabilities that was included in earnings for the period. This includes changes in market values for assets and liabilities accounted for at fair value and impairments on loans held-for-sale and real estate owned. This excludes valuation adjustments recorded in Mortgage Banking Activities, Net.

+ References

No definition available.

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- Definition

Securities Financed Through Nonrecourse Resecuritization

+ References

No definition available.

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27198-111563

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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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 210.5-02.2)

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

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- Definition

For investments which are quantified by principal amount, the principle balance held at close of period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 4

-Subparagraph (SX 210.12-12C.Column B)

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-Topic 946

-SubTopic 320

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-Paragraph 6

-Subparagraph (SX 210.12-14.Column B)

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-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-12.Column B)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 12C

-Paragraph Column B

-Article 12

Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

-Section 12

-Paragraph Column B

-Article 12

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-Name Regulation S-X (SX)

-Number 210

-Section 14

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- Definition

The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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- Definition

Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

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-Paragraph 1

-Subparagraph (SX 210.9-03.4)

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Real Estate Securities - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014 Investment	Dec. 31, 2013 Investment	Dec. 31, 2012
Investment Holdings [Line Items]
Trading securities	$ 111,606,000us-gaap_TradingSecurities	$ 124,555,000us-gaap_TradingSecurities
Number of AFS securities	290rwt_NumberOfAvailableForSaleSecurities	303rwt_NumberOfAvailableForSaleSecurities
Number of securities in unrealized loss position	31	76
Number of securities in a continuous unrealized loss position for twelve consecutive months or longer	10	5
Gross unrealized losses on AFS securities	3,000,000
Other than temporary impairment loss on AFS securities	5,000,000
Other market valuation adjustments	(10,146,000)rwt_OtherMarketValuationAdjustments	(5,709,000)rwt_OtherMarketValuationAdjustments	1,539,000rwt_OtherMarketValuationAdjustments
Residential
Investment Holdings [Line Items]
Marketable securities, due from five to ten years	2,000,000
Marketable securities, less than five years	8,000,000
Interest Only Securities
Investment Holdings [Line Items]
Trading securities	96,000,000
Senior Securities
Investment Holdings [Line Items]
Trading securities	101,753,000	119,575,000
Senior Securities \| Trading Securities
Investment Holdings [Line Items]
Trading securities	6,000
Senior Securities \| Prime
Investment Holdings [Line Items]
Trading securities	93,802,000	110,505,000
Securities financed through non-recourse resecuritization entity	105,000,000	131,000,000
Senior Securities \| Non-prime
Investment Holdings [Line Items]
Trading securities	7,951,000	9,070,000
Securities financed through non-recourse resecuritization entity	117,000,000	132,000,000
Residential Subordinate Securities
Investment Holdings [Line Items]
Trading securities	10,000,000
Residential Subordinate Securities \| Trading Securities
Investment Holdings [Line Items]
Unpaid principal balance	21,000,000
Residential Senior and Subordinate Securities \| Trading Securities
Investment Holdings [Line Items]
Unpaid principal balance	6,000,000
Available-for-sale Securities
Investment Holdings [Line Items]
Other market valuation adjustments	$ 1,000,000