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AGREEMENT AND PLAN OF MERGER (Details) - Alloy Parent and Alloy Merger Sub $ / shares in Units, $ in Millions | May 05, 2024 USD ($) d $ / shares
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Subsequent Event [Line Items] |
Conversion price, cash (in usd per share) | $ / shares | $ 67.00
Equity value of ALLETE common stock acquired | $ 3,900
Maximum conversion window | d | 5
Alloy Parent |
Subsequent Event [Line Items] |
Required amount to purchase of preferred stock | $ 300

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