Long-Term Debt	6 Months Ended
Jun. 30, 2015
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt FHLBC Borrowings In July 2014, our FHLB member subsidiary entered into a borrowing agreement with the Federal Home Loan Bank of Chicago. As of June 30, 2015, under this agreement, our subsidiary could incur borrowings up to $1 billion, also referred to as “advances,” from the FHLBC secured by eligible collateral, including, but not limited to residential mortgage loans and residential mortgage-backed securities. This borrowing agreement is uncommitted, which means that any request we make to borrow funds may be declined for any reason, even if at the time of the borrowing request we have then-outstanding borrowings that are less than the borrowing limits under this agreement. During the three and six months ended June 30, 2015, our FHLB-member subsidiary borrowed an additional $31 million and $386 million, respectively, under this agreement. At June 30, 2015, $882 million of advances were outstanding under this agreement with a weighted average interest rate of 0.23% and a weighted average maturity of 6 years. Advances under this agreement incur interest charges based on a specified margin over the FHLBC’s 13-week discount note rate, which resets every 13 weeks. These advances were secured by residential mortgage loans with a fair value of $1.00 billion at June 30, 2015. This agreement also requires our subsidiary to purchase and hold stock in the FHLBC in an amount equal to a specified percentage of outstanding advances. At June 30, 2015, our subsidiary held $30 million of FHLBC stock that is included in other assets in our consolidated balance sheets. During July of 2015, the FHLBC approved an increase to our FHLB-member subsidiary's uncommitted borrowing capacity, bringing our subsidiary's total uncommitted borrowing capacity with the FHLBC to $1.4 billion. Commercial Secured Borrowing At June 30, 2015, we had commercial secured borrowings of $65 million resulting from transfers of portions of senior commercial mortgage loans to third parties that did not meet the criteria for sale treatment under GAAP and were accounted for as financings. We bifurcated certain of our senior commercial mortgage loans into a senior portion that was sold to a third party and a junior portion that we retained as an investment. Although GAAP requires us to record a secured borrowing liability when we receive cash from selling the senior portion of the loan, the liability has no economic substance to us in that it does not require periodic interest payments and has no maturity. For each commercial secured borrowing, at such time that the associated senior portion of the loan is repaid or we sell our retained junior portion, the secured borrowing liability and associated senior portion of the loan would be derecognized from our balance sheet. Convertible Notes In November 2014, RWT Holdings, Inc., a wholly-owned subsidiary of Redwood Trust, Inc., issued $205 million principal amount of 5.625% exchangeable senior notes due 2019. These exchangeable notes require semi-annual interest payments at a fixed coupon rate of 5.625% until maturity or exchange, which will be no later than November 15, 2019. After deducting the underwriting discount and offering costs, we received $198 million of net proceeds. Including amortization of deferred securities issuance costs, the interest expense yield on these exchangeable notes was 6.58% and 6.51% for the three and six months ended June 30, 2015, respectively. At June 30, 2015, the accrued interest payable balance on this debt was $2 million and the unamortized deferred issuance costs were $6 million. At June 30, 2015, these notes were exchangeable at the option of the holder at an exchange rate of 46.1798 common shares per $1,000 principal amount of exchangeable senior notes (equivalent to an exchange price of $21.65 per common share). Upon exchange of these notes by a holder, the holder will receive shares of our common stock. In March 2013, we issued $288 million principal amount of 4.625% convertible senior notes due 2018. These convertible notes require semi-annual interest payments at a fixed coupon rate of 4.625% until maturity or conversion, which will be no later than April 15, 2018. After deducting the underwriting discount and offering costs, we received $279 million of net proceeds. Including amortization of deferred securities issuance costs, the interest expense yield on these convertible notes was 5.41% and 5.39% for the three and six months ended June 30, 2015, respectively. At June 30, 2015, the accrued interest payable balance on this debt was $3 million and the unamortized deferred issuance costs were $5 million. At June 30, 2015, these notes were convertible at the option of the holder at a conversion rate of 41.1320 common shares per $1,000 principal amount of convertible senior notes (equivalent to a conversion price of $24.31 per common share). Upon conversion of these notes by a holder, the holder will receive shares of our common stock. Trust Preferred Securities and Subordinated Notes At June 30, 2015, we had trust preferred securities and subordinated notes outstanding of $100 million and $40 million, respectively. The interest expense yield on both our trust preferred securities and subordinated notes was 2.63% and 2.67% for the three months ended June 30, 2015 and 2014, respectively. Including hedging costs and amortization of deferred securities issuance costs, the interest expense yield on both our trust preferred securities and subordinated notes was 6.85% and 6.89% for the three months ended June 30, 2015 and 2014, respectively. The interest expense yield on both our trust preferred securities and subordinated notes was 2.58% and 2.57% for the six months ended June 30, 2015 and 2014, respectively. Including hedging costs and amortization of deferred securities issuance costs, the interest expense yield on both our trust preferred securities and subordinated notes was 6.85% and 6.87% for the six months ended June 30, 2015 and 2014, respectively. At both June 30, 2015 and December 31, 2014, the accrued interest payable balance on our trust preferred securities and subordinated notes was less than $1 million. Under the terms of this debt, we covenant, among other things, to use our best efforts to continue to qualify as a REIT. If an event of default were to occur in respect of this debt, we would generally be restricted under its terms (subject to certain exceptions) from making dividend distributions to stockholders, from repurchasing common stock or repurchasing or redeeming any other then-outstanding equity securities, and from making any other payments in respect of any equity interests in us or in respect of any then-outstanding debt that is pari passu or subordinate to this debt.

Long-Term Debt

FHLBC Borrowings

In July 2014, our FHLB member subsidiary entered into a borrowing agreement with the Federal Home Loan Bank of Chicago. As of June 30, 2015, under this agreement, our subsidiary could incur borrowings up to $1 billion, also referred to as “advances,” from the FHLBC secured by eligible collateral, including, but not limited to residential mortgage loans and residential mortgage-backed securities. This borrowing agreement is uncommitted, which means that any request we make to borrow funds may be declined for any reason, even if at the time of the borrowing request we have then-outstanding borrowings that are less than the borrowing limits under this agreement. During the three and six months ended June 30, 2015, our FHLB-member subsidiary borrowed an additional $31 million and $386 million, respectively, under this agreement. At June 30, 2015, $882 million of advances were outstanding under this agreement with a weighted average interest rate of 0.23% and a weighted average maturity of 6 years. Advances under this agreement incur interest charges based on a specified margin over the FHLBC’s 13-week discount note rate, which resets every 13 weeks. These advances were secured by residential mortgage loans with a fair value of $1.00 billion at June 30, 2015. This agreement also requires our subsidiary to purchase and hold stock in the FHLBC in an amount equal to a specified percentage of outstanding advances. At June 30, 2015, our subsidiary held $30 million of FHLBC stock that is included in other assets in our consolidated balance sheets. During July of 2015, the FHLBC approved an increase to our FHLB-member subsidiary's uncommitted borrowing capacity, bringing our subsidiary's total uncommitted borrowing capacity with the FHLBC to $1.4 billion.

Commercial Secured Borrowing

At June 30, 2015, we had commercial secured borrowings of $65 million resulting from transfers of portions of senior commercial mortgage loans to third parties that did not meet the criteria for sale treatment under GAAP and were accounted for as financings. We bifurcated certain of our senior commercial mortgage loans into a senior portion that was sold to a third party and a junior portion that we retained as an investment. Although GAAP requires us to record a secured borrowing liability when we receive cash from selling the senior portion of the loan, the liability has no economic substance to us in that it does not require periodic interest payments and has no maturity. For each commercial secured borrowing, at such time that the associated senior portion of the loan is repaid or we sell our retained junior portion, the secured borrowing liability and associated senior portion of the loan would be derecognized from our balance sheet.

Convertible Notes

In November 2014, RWT Holdings, Inc., a wholly-owned subsidiary of Redwood Trust, Inc., issued $205 million principal amount of 5.625% exchangeable senior notes due 2019. These exchangeable notes require semi-annual interest payments at a fixed coupon rate of 5.625% until maturity or exchange, which will be no later than November 15, 2019. After deducting the underwriting discount and offering costs, we received $198 million of net proceeds. Including amortization of deferred securities issuance costs, the interest expense yield on these exchangeable notes was 6.58% and 6.51% for the three and six months ended June 30, 2015, respectively. At June 30, 2015, the accrued interest payable balance on this debt was $2 million and the unamortized deferred issuance costs were $6 million. At June 30, 2015, these notes were exchangeable at the option of the holder at an exchange rate of 46.1798 common shares per $1,000 principal amount of exchangeable senior notes (equivalent to an exchange price of $21.65 per common share). Upon exchange of these notes by a holder, the holder will receive shares of our common stock.

In March 2013, we issued $288 million principal amount of 4.625% convertible senior notes due 2018. These convertible notes require semi-annual interest payments at a fixed coupon rate of 4.625% until maturity or conversion, which will be no later than April 15, 2018. After deducting the underwriting discount and offering costs, we received $279 million of net proceeds. Including amortization of deferred securities issuance costs, the interest expense yield on these convertible notes was 5.41% and 5.39% for the three and six months ended June 30, 2015, respectively. At June 30, 2015, the accrued interest payable balance on this debt was $3 million and the unamortized deferred issuance costs were $5 million. At June 30, 2015, these notes were convertible at the option of the holder at a conversion rate of 41.1320 common shares per $1,000 principal amount of convertible senior notes (equivalent to a conversion price of $24.31 per common share). Upon conversion of these notes by a holder, the holder will receive shares of our common stock.

Trust Preferred Securities and Subordinated Notes

At June 30, 2015, we had trust preferred securities and subordinated notes outstanding of $100 million and $40 million, respectively. The interest expense yield on both our trust preferred securities and subordinated notes was 2.63% and 2.67% for the three months ended June 30, 2015 and 2014, respectively. Including hedging costs and amortization of deferred securities issuance costs, the interest expense yield on both our trust preferred securities and subordinated notes was 6.85% and 6.89% for the three months ended June 30, 2015 and 2014, respectively.

The interest expense yield on both our trust preferred securities and subordinated notes was 2.58% and 2.57% for the six months ended June 30, 2015 and 2014, respectively. Including hedging costs and amortization of deferred securities issuance costs, the interest expense yield on both our trust preferred securities and subordinated notes was 6.85% and 6.87% for the six months ended June 30, 2015 and 2014, respectively.

At both June 30, 2015 and December 31, 2014, the accrued interest payable balance on our trust preferred securities and subordinated notes was less than $1 million. Under the terms of this debt, we covenant, among other things, to use our best efforts to continue to qualify as a REIT. If an event of default were to occur in respect of this debt, we would generally be restricted under its terms (subject to certain exceptions) from making dividend distributions to stockholders, from repurchasing common stock or repurchasing or redeeming any other then-outstanding equity securities, and from making any other payments in respect of any equity interests in us or in respect of any then-outstanding debt that is pari passu or subordinate to this debt.