Long-Term Debt	12 Months Ended
Dec. 31, 2020
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. At December 31, 2020, under this agreement, our subsidiary could incur borrowings, also referred to as "advances," from the FHLB secured by eligible collateral, including residential mortgage loans. Under a final rule published by the Federal Housing Finance Agency in January 2016, our FHLB-member subsidiary was permitted to remain an FHLB member through the five-year transition period for captive insurance companies that ended in February 2021. Our FHLB-member's existing $1 million of FHLB debt, which matures beyond this transition period, is permitted to remain outstanding until its stated maturity. 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. At December 31, 2020, $1 million of advances were outstanding under our FHLBC borrowing agreement, with a weighted average interest rate of 0.30%. These borrowings mature in 2026. At December 31, 2019, $2.00 billion of advances were outstanding under this agreement, which were classified as long-term debt, with a weighted average interest rate of 1.88% and a weighted average maturity of six years. During the year ended December 31, 2020, we repaid $2.0 billion of our FHLBC borrowings. At December 31, 2020, total advances under this agreement were secured by $1 million of restricted cash. We do not expect to increase borrowings under our FHLBC borrowing agreement above the existing $1 million of advances outstanding. 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 December 31, 2020, our subsidiary held $5 million of FHLBC stock that is included in Other assets in our consolidated balance sheets. Recourse Subordinate Securities Financing Facilities In 2019, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable (i.e., not subject to margin calls based on the market value of the underlying collateral that is non-delinquent) recourse debt financing of certain Sequoia securities as well as securities retained from our consolidated Sequoia Choice securitizations. The financing is fully and unconditionally guaranteed by Redwood, with an interest rate of approximately 4.21% through September 2022. The financing facility may be terminated, at our option, in September 2022, and has a final maturity in September 2024, provided that the interest rate on amounts outstanding under the facility increases between October 2022 and September 2024. At December 31, 2020, we had borrowings under this facility totaling $178 million and $1 million of unamortized deferred issuance costs, for a net carrying value of $177 million. At December 31, 2020, the fair value of real estate securities pledged as collateral under this long-term debt facility was $249 million and included Sequoia securities and securities retained from our Sequoia Choice securitizations. In the first quarter of 2020, a subsidiary of Redwood entered into a second repurchase agreement with similar terms to provide non-marginable recourse debt financing of certain securities retained from our consolidated CAFL securitizations. The financing is fully and unconditionally guaranteed by Redwood, with an interest rate of approximately 4.21% through February 2023. The financing facility may be terminated, at our option, in February 2023, and has a final maturity in February 2025, provided that the interest rate on amounts outstanding under the facility increases between March 2023 and February 2025. At December 31, 2020, we had borrowings under this facility totaling $103 million and $1 million of unamortized deferred issuance costs, for a net carrying value of $102 million. At December 31, 2020, the fair value of real estate securities pledged as collateral under this long-term debt facility was $114 million and included securities retained from our consolidated CAFL securitizations. Non-Recourse Business Purpose Loan Financing Facilities In the third quarter of 2020, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable, non-recourse financing primarily for business purpose bridge loans. Borrowings under this facility accrue interest at a per annum rate equal to one-month LIBOR plus 3.85% (with a 0.50% LIBOR floor), through July 2022. We do not have the ability to increase borrowings under this borrowing facility above the existing amounts outstanding. At December 31, 2020, we had borrowings under this facility totaling $115 million and $1 million of unamortized deferred issuance costs, for a net carrying value of $114 million. At December 31, 2020, $186 million of bridge loans were pledged as collateral under this facility. In the second quarter of 2020, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable, non-recourse financing primarily for business purpose bridge loans. Borrowings under this facility accrue interest at a per annum rate equal to one-month LIBOR plus 7.50% (with a 1.50% LIBOR floor), through June 2022 (facility is fully callable in June 2021). At December 31, 2020, this facility had an aggregate maximum borrowing capacity of $372 million, which consisted of a term facility of $197 million and a revolving facility of $175 million. The revolving period ends in June 2021, and amounts borrowed under the term and revolving facilities are due in full in June 2022. At December 31, 2020, we had borrowings under this facility totaling $252 million and $2 million of unamortized deferred issuance costs, for a net carrying value of $249 million. At December 31, 2020, $338 million of bridge loans and $21 million of other BPL investments were pledged as collateral under this facility. Recourse Business Purpose Loan Financing Facilities In the third quarter of 2020, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable financing for business purpose bridge loans and single-family rental loans. Borrowings under this facility accrue interest at a per annum rate equal to three-month LIBOR plus 3.00% through September 2023 and are recourse to Redwood. This facility has an aggregate maximum borrowing capacity of $250 million. At December 31, 2020, we had borrowings under this facility totaling $80 million and $0.2 million of unamortized deferred issuance costs, for a net carrying value of $80 million. At December 31, 2020, $106 million of single-family rental loans were pledged as collateral under this facility. In the second quarter of 2020, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable financing for business purpose bridge loans and single-family rental loans. Borrowings under this facility accrue interest at a per annum rate equal to three-month LIBOR plus 3.00% to 3.50% (with a 1.00% LIBOR floor) through May 2022 and are recourse to Redwood. This facility has an aggregate maximum borrowing capacity of $350 million. At December 31, 2020, we had borrowings under this facility totaling $52 million and $0.5 million of unamortized deferred issuance costs, for a net carrying value of $51 million. At December 31, 2020, $24 million of bridge loans and $49 million of single-family rental loans were pledged as collateral under this facility. Recourse Revolving Debt Facility In the first quarter of 2020, a subsidiary of Redwood entered into a secured revolving debt facility agreement collateralized by MSRs and certificated mortgage servicing rights. Borrowings under this facility accrue interest at a per annum rate equal to one-month LIBOR plus 3.00% through January 2021, with an increase in rate between February 2021 and the maturity of the facility in January 2022. This facility has an aggregate maximum borrowing capacity of $50 million. We had no borrowings outstanding under this facility at December 31, 2020. Convertible Notes In September 2019, RWT Holdings, Inc., a wholly-owned subsidiary of Redwood Trust, Inc., issued $201 million principal amount of 5.75% exchangeable senior notes due 2025. These exchangeable notes require semi-annual interest payments at a fixed coupon rate of 5.75% until maturity or exchange, which will be no later than October 1, 2025. After deducting the underwriting discount and offering costs, we received $195 million of net proceeds. Including amortization of deferred debt issuance costs, the weighted average interest expense yield on these exchangeable notes is approximately 6.3% per annum. At December 31, 2020, these notes were exchangeable at the option of the holder at an exchange rate of 55.2644 common shares per $1,000 principal amount of exchangeable senior notes (equivalent to an exchange price of $18.09 per common share). Upon exchange of these notes by a holder, the holder will receive shares of our common stock. During the second quarter of 2020, we repurchased $29 million par value of these notes at a discount and recorded a gain on extinguishment of $6 million in Realized gains, net on our consolidated statements of income (loss). At December 31, 2020, the outstanding principal amount of these notes was $172 million. At December 31, 2020, the accrued interest payable balance on this debt was $2 million and the unamortized deferred issuance costs were $4 million. In June 2018, we issued $200 million principal amount of 5.625% convertible senior notes due 2024 at an issuance price of 99.5%. These convertible notes require semi-annual interest payments at a fixed coupon rate of 5.625% until maturity or conversion, which will be no later than July 15, 2024. After deducting the issuance discount, the underwriting discount and offering costs, we received $194 million of net proceeds. Including amortization of deferred debt issuance costs and the debt discount, the weighted average interest expense yield on these convertible notes is approximately 6.2% per annum. These notes are convertible at the option of the holder at a conversion rate of 54.8317 common shares per $1,000 principal amount of convertible senior notes (equivalent to a conversion price of $18.24 per common share). Upon conversion of these notes by a holder, the holder will receive shares of our common stock. During the second quarter of 2020, we repurchased $50 million par value of these notes at a discount and recorded a gain on extinguishment of $9 million in Realized gains, net on our consolidated statements of income (loss). At December 31, 2020, the outstanding principal amount of these notes was $150 million and the accrued interest payable on this debt was $4 million. At December 31, 2020, the unamortized deferred issuance costs and debt discount were $2 million and $0.5 million, respectively. In August 2017, we issued $245 million principal amount of 4.75% convertible senior notes due 2023. These convertible notes require semi-annual interest payments at a fixed coupon rate of 4.75% until maturity or conversion, which will be no later than August 15, 2023. After deducting the underwriting discount and offering costs, we received $238 million of net proceeds. Including amortization of deferred debt issuance costs, the weighted average interest expense yield on these convertible notes is approximately 5.3% per annum. At December 31, 2020, these notes were convertible at the option of the holder at a conversion rate of 54.4764 common shares per $1,000 principal amount of convertible senior notes (equivalent to a conversion price of $18.36 per common share). Upon conversion of these notes by a holder, the holder will receive shares of our common stock. During the second quarter of 2020, we repurchased $46 million par value of these notes at a discount and recorded a gain on extinguishment of $10 million in Realized gains, net on our consolidated statements of income (loss). At December 31, 2020, the outstanding principal amount of these notes was $199 million. At December 31, 2020, the accrued interest payable balance on this debt was $4 million and the unamortized deferred issuance costs were $3 million. Trust Preferred Securities and Subordinated Notes At December 31, 2020, we had trust preferred securities and subordinated notes outstanding of $100 million and $40 million, respectively. This debt requires quarterly interest payments at a floating rate equal to three-month LIBOR plus 2.25% until the notes are redeemed. The $100 million trust preferred securities will be redeemed no later than January 30, 2037, and the $40 million subordinated notes will be redeemed no later than July 30, 2037. At both December 31, 2020 and December 31, 2019, the accrued interest payable balance on our trust preferred securities and subordinated notes was $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.

In July 2014, our FHLB-member subsidiary entered into a borrowing agreement with the Federal Home Loan Bank of Chicago. At December 31, 2020, under this agreement, our subsidiary could incur borrowings, also referred to as "advances," from the FHLB secured by eligible collateral, including residential mortgage loans. Under a final rule published by the Federal Housing Finance Agency in January 2016, our FHLB-member subsidiary was permitted to remain an FHLB member through the five-year transition period for captive insurance companies that ended in February 2021. Our FHLB-member's existing $1 million of FHLB debt, which matures beyond this transition period, is permitted to remain outstanding until its stated maturity. 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.

At December 31, 2020, $1 million of advances were outstanding under our FHLBC borrowing agreement, with a weighted average interest rate of 0.30%. These borrowings mature in 2026. At December 31, 2019, $2.00 billion of advances were outstanding under this agreement, which were classified as long-term debt, with a weighted average interest rate of 1.88% and a weighted average maturity of six years. During the year ended December 31, 2020, we repaid $2.0 billion of our FHLBC borrowings. At December 31, 2020, total advances under this agreement were secured by $1 million of restricted cash. We do not expect to increase borrowings under our FHLBC borrowing agreement above the existing $1 million of advances outstanding. 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 December 31, 2020, our subsidiary held $5 million of FHLBC stock that is included in Other assets in our consolidated balance sheets.

In 2019, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable (i.e., not subject to margin calls based on the market value of the underlying collateral that is non-delinquent) recourse debt financing of certain Sequoia securities as well as securities retained from our consolidated Sequoia Choice securitizations. The financing is fully and unconditionally guaranteed by Redwood, with an interest rate of approximately 4.21% through September 2022. The financing facility may be terminated, at our option, in September 2022, and has a final maturity in September 2024, provided that the interest rate on amounts outstanding under the facility increases between October 2022 and September 2024. At December 31, 2020, we had borrowings under this facility totaling $178 million and $1 million of unamortized deferred issuance costs, for a net carrying value of $177 million. At December 31, 2020, the fair value of real estate securities pledged as collateral under this long-term debt facility was $249 million and included Sequoia securities and securities retained from our Sequoia Choice securitizations.

In the first quarter of 2020, a subsidiary of Redwood entered into a second repurchase agreement with similar terms to provide non-marginable recourse debt financing of certain securities retained from our consolidated CAFL securitizations. The financing is fully and unconditionally guaranteed by Redwood, with an interest rate of approximately 4.21% through February 2023. The financing facility may be terminated, at our option, in February 2023, and has a final maturity in February 2025, provided that the interest rate on amounts outstanding under the facility increases between March 2023 and February 2025. At December 31, 2020, we had borrowings under this facility totaling $103 million and $1 million of unamortized deferred issuance costs, for a net carrying value of $102 million. At December 31, 2020, the fair value of real estate securities pledged as collateral under this long-term debt facility was $114 million and included securities retained from our consolidated CAFL securitizations.

In the third quarter of 2020, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable, non-recourse financing primarily for business purpose bridge loans. Borrowings under this facility accrue interest at a per annum rate equal to one-month LIBOR plus 3.85% (with a 0.50% LIBOR floor), through July 2022. We do not have the ability to increase borrowings under this borrowing facility above the existing amounts outstanding. At December 31, 2020, we had borrowings under this facility totaling $115 million and $1 million of unamortized deferred issuance costs, for a net carrying value of $114 million. At December 31, 2020, $186 million of bridge loans were pledged as collateral under this facility.

In the second quarter of 2020, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable, non-recourse financing primarily for business purpose bridge loans. Borrowings under this facility accrue interest at a per annum rate equal to one-month LIBOR plus 7.50% (with a 1.50% LIBOR floor), through June 2022 (facility is fully callable in June 2021). At December 31, 2020, this facility had an aggregate maximum borrowing capacity of $372 million, which consisted of a term facility of $197 million and a revolving facility of $175 million. The revolving period ends in June 2021, and amounts borrowed under the term and revolving facilities are due in full in June 2022. At December 31, 2020, we had borrowings under this facility totaling $252 million and $2 million of unamortized deferred issuance costs, for a net carrying value of $249 million. At December 31, 2020, $338 million of bridge loans and $21 million of other BPL investments were pledged as collateral under this facility.

In the third quarter of 2020, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable financing for business purpose bridge loans and single-family rental loans. Borrowings under this facility accrue interest at a per annum rate equal to three-month LIBOR plus 3.00% through September 2023 and are recourse to Redwood. This facility has an aggregate maximum borrowing capacity of $250 million. At December 31, 2020, we had borrowings under this facility totaling $80 million and $0.2 million of unamortized deferred issuance costs, for a net carrying value of $80 million. At December 31, 2020, $106 million of single-family rental loans were pledged as collateral under this facility.

In the second quarter of 2020, a subsidiary of Redwood entered into a repurchase agreement providing non-marginable financing for business purpose bridge loans and single-family rental loans. Borrowings under this facility accrue interest at a per annum rate equal to three-month LIBOR plus 3.00% to 3.50% (with a 1.00% LIBOR floor) through May 2022 and are recourse to Redwood. This facility has an aggregate maximum borrowing capacity of $350 million. At December 31, 2020, we had borrowings under this facility totaling $52 million and $0.5 million of unamortized deferred issuance costs, for a net carrying value of $51 million. At December 31, 2020, $24 million of bridge loans and $49 million of single-family rental loans were pledged as collateral under this facility.

In the first quarter of 2020, a subsidiary of Redwood entered into a secured revolving debt facility agreement collateralized by MSRs and certificated mortgage servicing rights. Borrowings under this facility accrue interest at a per annum rate equal to one-month LIBOR plus 3.00% through January 2021, with an increase in rate between February 2021 and the maturity of the facility in January 2022. This facility has an aggregate maximum borrowing capacity of $50 million. We had no borrowings outstanding under this facility at December 31, 2020.

In September 2019, RWT Holdings, Inc., a wholly-owned subsidiary of Redwood Trust, Inc., issued $201 million principal amount of 5.75% exchangeable senior notes due 2025. These exchangeable notes require semi-annual interest payments at a fixed coupon rate of 5.75% until maturity or exchange, which will be no later than October 1, 2025. After deducting the underwriting discount and offering costs, we received $195 million of net proceeds. Including amortization of deferred debt issuance costs, the weighted average interest expense yield on these exchangeable notes is approximately 6.3% per annum. At December 31, 2020, these notes were exchangeable at the option of the holder at an exchange rate of 55.2644 common shares per $1,000 principal amount of exchangeable senior notes (equivalent to an exchange price of $18.09 per common share). Upon exchange of these notes by a holder, the holder will receive shares of our common stock. During the second quarter of 2020, we repurchased $29 million par value of these notes at a discount and recorded a gain on extinguishment of $6 million in Realized gains, net on our consolidated statements of income (loss). At December 31, 2020, the outstanding principal amount of these notes was $172 million. At December 31, 2020, the accrued interest payable balance on this debt was $2 million and the unamortized deferred issuance costs were $4 million.

In June 2018, we issued $200 million principal amount of 5.625% convertible senior notes due 2024 at an issuance price of 99.5%. These convertible notes require semi-annual interest payments at a fixed coupon rate of 5.625% until maturity or conversion, which will be no later than July 15, 2024. After deducting the issuance discount, the underwriting discount and offering costs, we received $194 million of net proceeds. Including amortization of deferred debt issuance costs and the debt discount, the weighted average interest expense yield on these convertible notes is approximately 6.2% per annum. These notes are convertible at the option of the holder at a conversion rate of 54.8317 common shares per $1,000 principal amount of convertible senior notes (equivalent to a conversion price of $18.24 per common share). Upon conversion of these notes by a holder, the holder will receive shares of our common stock. During the second quarter of 2020, we repurchased $50 million par value of these notes at a discount and recorded a gain on extinguishment of $9 million in Realized gains, net on our consolidated statements of income (loss). At December 31, 2020, the outstanding principal amount of these notes was $150 million and the accrued interest payable on this debt was $4 million. At December 31, 2020, the unamortized deferred issuance costs and debt discount were $2 million and $0.5 million, respectively.

In August 2017, we issued $245 million principal amount of 4.75% convertible senior notes due 2023. These convertible notes require semi-annual interest payments at a fixed coupon rate of 4.75% until maturity or conversion, which will be no later than August 15, 2023. After deducting the underwriting discount and offering costs, we received $238 million of net proceeds. Including amortization of deferred debt issuance costs, the weighted average interest expense yield on these convertible notes is approximately 5.3% per annum. At December 31, 2020, these notes were convertible at the option of the holder at a conversion rate of 54.4764 common shares per $1,000 principal amount of convertible senior notes (equivalent to a conversion price of $18.36 per common share). Upon conversion of these notes by a holder, the holder will receive shares of our common stock. During the second quarter of 2020, we repurchased $46 million par value of these notes at a discount and recorded a gain on extinguishment of $10 million in Realized gains, net on our consolidated statements of income (loss). At December 31, 2020, the outstanding principal amount of these notes was $199 million. At December 31, 2020, the accrued interest payable balance on this debt was $4 million and the unamortized deferred issuance costs were $3 million.

At December 31, 2020, we had trust preferred securities and subordinated notes outstanding of $100 million and $40 million, respectively. This debt requires quarterly interest payments at a floating rate equal to three-month LIBOR plus 2.25% until the notes are redeemed. The $100 million trust preferred securities will be redeemed no later than January 30, 2037, and the $40 million subordinated notes will be redeemed no later than July 30, 2037. At both December 31, 2020 and December 31, 2019, the accrued interest payable balance on our trust preferred securities and subordinated notes was $1 million.