A new set of federal documents released Thursday proves that Elon Musk has lined up$46.5 billion in financing to back his unsolicited bid for Twitter. The new details demonstrate that Musk is serious about his plans to take the social media platform private. 

New and updated filings with the US Securities and Exchange Commission show Musk plans to pay for the acquisition with$25.5 billion in loans (including$12.5 billion in margin loans), as well as$21 billion from equity financing. 

Last week, Twitter's board of directors expressed their opposition to Musk's offer by unanimously adopting a shareholder rights plan. Should Musk or anyone else acquire 15% or more of Twitter's outstanding common stock, the board would offer other shareholders more stock at a discounted price. That would dilute Musk's stake in the company. 

Musk has so far been coy as to whether he would pursue a tender offer to acquire Twitter -- one of his recent tweets suggested he might. If he were to do so, he would simply buy shares up from public shareholders. The SEC paperwork says Musk "has not commenced, or determined to commence, any tender offer for Shares of Twitter" but that he "may, directly or indirectly, take such additional steps as he may deem appropriate to further the Proposal or the Potential Offer."

The CEO has said his interest in the company isn't financial. "I invested in Twitter as I believe in its potential to be the platform for free speech around the globe, and I believe free speech is a societal imperative for a functioning democracy," he initially wrote in an SEC filing.