| Cover | Jul. 20, 2023 |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jul. 20, 2023 |
| Entity File Number | 001-40633 |
| Entity Registrant Name | TORTOISEECOFIN ACQUISITION CORP. III |
| Entity Central Index Key | 0001847112 |
| Entity Tax Identification Number | 98-1583266 |
| Entity Incorporation, State or Country Code | E9 |
| Entity Address, Address Line One | 6363 College Boulevard |
| Entity Address, City or Town | Overland Park |
| Entity Address, State or Province | KS |
| Entity Address, Postal Zip Code | 66211 |
| City Area Code | 913 |
| Local Phone Number | 981-1020 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | false |
| Units, each consisting of one share of Class A Ordinary Share, $0.0001 par value, and one-fourth of one redeemable warrant | |
| Title of 12(b) Security | Units, each consisting of one share of Class A Ordinary Share, $0.0001 par value, and one-fourth of one redeemable warrant |
| Trading Symbol | TRTL.U |
| Security Exchange Name | NYSE |
| Class A Ordinary Shares included as part of the units | |
| Title of 12(b) Security | Class A Ordinary Shares included as part of the units |
| Trading Symbol | TRTL |
| Security Exchange Name | NYSE |
| Redeemable warrants included as part of the units, each whole warrant exercisable for one Class A Ordinary Share at an exercise price of $11.50 | |
| Title of 12(b) Security | Redeemable warrants included as part of the units, each whole warrant exercisable for one Class A Ordinary Share at an exercise price of $11.50 |
| Trading Symbol | TRTL WS |
| Security Exchange Name | NYSE |
