| Document and Entity Information | Mar. 16, 2022 |
| Document And Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Mar. 16, 2022 |
| Entity Registrant Name | SPARTAN ACQUISITION CORP. III |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-40022 |
| Entity Tax Identification Number | 86-1182458 |
| Entity Address, Address Line One | Westervoortsedijk 73 KB |
| Entity Address, Postal Zip Code | 6827 AV |
| Entity Address, City or Town | Arnhem |
| Entity Address, Country | NL |
| Country Region | 31 |
| City Area Code | (0) 88 |
| Local Phone Number | 7500-300 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Current Fiscal Year End Date | --12-31 |
| Amendment Flag | false |
| Entity Central Index Key | 0001838527 |
| Capital Units [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Units, each consisting of one share of Class A Common Stock and one-fourth of one warrant |
| Trading Symbol | SPAQ.U |
| Security Exchange Name | NYSE |
| Common Class A [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Class A Common Stock, par value $0.0001 per share |
| Trading Symbol | SPAQ |
| Security Exchange Name | NYSE |
| Warrant [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Warrants, each whole warrant exercisable for one share of Class A Common Stock at an exercise price of $11.50 per share |
| Trading Symbol | SPAQ.WS |
| Security Exchange Name | NYSE |
