| Submission | Feb. 27, 2025 |
| Submission [Line Items] | |
| Central Index Key | 0001636282 |
| Registrant Name | Spyre Therapeutics, Inc. |
| Form Type | S-3 |
| Submission Type | S-3 |
| Fee Exhibit Type | EX-FILING FEES |
| Offerings | Feb. 27, 2025 USD ($) |
| Offering: 1 | |
| Offering: | |
| Rule 457(o) | true |
| Security Type | Equity |
| Security Class Title | Common stock, $0.0001 par value per share |
| Fee Rate | 0.01531% |
| Offering: 2 | |
| Offering: | |
| Rule 457(o) | true |
| Security Type | Equity |
| Security Class Title | Preferred stock, $0.0001 par value per share |
| Fee Rate | 0.01531% |
| Offering: 3 | |
| Offering: | |
| Rule 457(o) | true |
| Security Type | Debt |
| Security Class Title | Debt Securities |
| Fee Rate | 0.01531% |
| Offering: 4 | |
| Offering: | |
| Rule 457(o) | true |
| Security Type | Other |
| Security Class Title | Warrants |
| Fee Rate | 0.01531% |
| Offering: 5 | |
| Offering: | |
| Rule 457(o) | true |
| Security Type | Other |
| Security Class Title | Units |
| Fee Rate | 0.01531% |
| Offering: 6 | |
| Offering: | |
| Fee Previously Paid | false |
| Rule 457(o) | true |
| Security Type | Unallocated (Universal) Shelf |
| Maximum Aggregate Offering Price | $ 430,071,875 |
| Fee Rate | 0.01531% |
| Amount of Registration Fee | $ 65,844 |
| Offering Note | (a) The amount to be registered consists of up to $500,000,000 of an indeterminate amount of common stock, preferred stock, debt securities, warrants and/or units. There is also being registered hereunder such currently indeterminate number of (i) shares of common stock or other securities of the registrant as may be issued upon conversion of, or in exchange for, convertible or exchangeable debt securities and/or preferred stock registered hereby, or (ii) shares of preferred stock, common stock, debt securities or units as may be issued upon exercise of warrants registered hereby, as the case may be. Any securities registered hereunder may be sold separately or as units with the other securities registered hereunder. (b) The proposed maximum aggregate offering price per unit will be determined from time to time by the registrant in connection with the issuance by the registrant of the securities registered hereunder and is not specified as to each class of security pursuant to General Instruction II.D. of Form S-3 under the Securities Act of 1933, as amended (the "Securities Act"). (c) Estimated solely for purposes of computing the registration fee pursuant to Rule 457(o) under the Securities Act. In no event will the aggregate offering price of all securities sold by the registrant from time to time pursuant to this registration statement exceed $500,000,000. No separate consideration will be received for (i) common stock or other securities of the registrant that may be issued upon conversion of, or in exchange for, convertible or exchangeable debt securities and/or preferred stock registered hereby, or (ii) preferred stock, common stock, debt securities or units that may be issued upon exercise of warrants registered hereby, as the case may be. |
| Offering: 7 | |
| Offering: | |
| Rule 415(a)(6) | true |
| Security Type | Other |
| Security Class Title | Unallocated (Universal) Shelf |
| Maximum Aggregate Offering Price | $ 69,928,125 |
| Carry Forward Form Type | S-3 |
| Carry Forward File Number | 333-281975 |
| Carry Forward Initial Effective Date | Sep. 18, 2024 |
| Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward | $ 10,321.39 |
| Offering Note | Pursuant to Rule 415(a)(6) under the Securities Act, securities with a maximum aggregate price of $69,928,125 registered hereunder are unsold securities (the "Unsold Securities") previously covered by the registrant's registration statement on Form S-3 (File No. 333-281975) which was initially filed with the Securities and Exchange Commission on September 6, 2024 and became effective on September 18, 2024 (the "Prior Registration Statement"), and are included in this registration statement. The registrant paid a filing fee of $10,321.39 (calculated at the filing fee rate in effect at the time of the filing of the Prior Registration Statement) relating to the Unsold Securities under the Prior Registration Statement. The registrant may continue to offer and sell under the Prior Registration Statement the Unsold Securities being registered hereunder. To the extent that, after the filing date hereof and prior to the effectiveness of this registration statement, the registrant sells any Unsold Securities under the Prior Registration Statement, the registrant will identify in a pre-effective amendment to this registration statement the updated number of Unsold Securities from the Prior Registration Statement to be included in this registration statement pursuant to Rule 415(a)(6) and the updated amount of new securities to be registered on this registration statement. Pursuant to Rule 415(a)(6) under the Securities Act, the offering of Unsold Securities under the Prior Registration Statement will be deemed terminated as of the date of effectiveness of this registration statement. |
| Fees Summary | Feb. 27, 2025 USD ($) |
| Fees Summary [Line Items] | |
| Total Offering | $ 500,000,000 |
| Previously Paid Amount | 0 |
| Total Fee Amount | 65,844 |
| Total Offset Amount | 0 |
| Net Fee | $ 65,844 |
