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Merger Agreement - Additional Information (Details Textual) | Apr. 20, 2024 USD ($) | Apr. 03, 2024 USD ($) Member $ / shares shares | Jun. 30, 2024 USD ($)
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Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Declared cash dividend |  | $ 5,000,000 |
Amount after cash dividend declared |  | $ 20,000,000 |
Amount of retention bonuses |  |  | $ 444,000
ARCA and Oruka |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Percentage of ownership interest |  | 97.61% |
Series B Preferred Stock |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Minimum percentage of originally issued shares |  | 30.00% |
Minimum percentage of originally issued outstanding |  | 30.00% |
Merger Agreement | ARCA and Oruka |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Payment of other party termination fee |  | $ 440,000 |
Merger Agreement | Minimum |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Subscription agreement receipt of proceeds amount |  | $ 175,000,000 |
Merger Agreement | Series B Preferred Stock |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Preferred stock, par value | $ / shares |  | $ 0.001 |
Seperation Agreement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Number of months base salary |  | 12 months |
Cash payment |  | $ 25,000 |
Second Amendment of Certain Retention Bonus Letters | Thomas A. Keuer |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Increase of retention bonus to each executive | $ 200,000 |  |
Second Amendment of Certain Retention Bonus Letters | C. Jeffrey Dekker |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Increase of retention bonus to each executive | 200,000 |  |
Original Terms of Retention Bonus Letter and First Amendment to Retention Bonus Letter | Thomas A. Keuer and C. Jeffrey Dekker |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Amount of retention bonuses | $ 165,000 |  |
Oruka Therapeutics Inc | Common Stock and Pre Funded Warrants |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Aggregate purchase price |  | $ 275,000,000 |
Oruka Therapeutics Inc | First Merger |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Excepted number of board members | Member |  | 6 |
ARCA |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Number of consecutive trading days |  | 5 days |
Adjusted exchange ratio |  | $ 5,000,000 |
ARCA | Common Stock |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Initially specified percentage for beneficial number of shares |  | 9.99% |
ARCA | ARCA and Oruka |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Percentage of noncontrolling ownership interest |  | 2.39% |
ARCA | First Merger | Series B Preferred Stock | Common Stock |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Preferred stock convertible shares issuable | shares |  | 1,000 |

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