Detroit multibillionaire Dan Gilbert, the Cleveland Cavaliers owner who established mortgage group Quicken Loans more than three decades ago, took Quicken's parent, Rocket Companies, public on the New York Stock Exchange on Thursday, significantly boosting his wealth.

With shares trading at $19.30 around noontime, Gilbert's 95 percent equity stake in Rocket Companies is valued at $36.4 billion. He also disposed of $1.76 billion of Rocket Companies shares in the initial public bid.

The latest IPO makes Gilbert one of the most prominent beneficiaries of an era of ultra-low interest rates and highlights a career that has seen him rise from delivering pizzas to rubbing elbows with Berkshire Hathaway big boss Warren Buffett, winning an NBA title and emerging as a figurehead for the evolution of central Detroit.

Gilbert owns the Cleveland Cavaliers NBA team and a substantial volume of real estate in Detroit. With all his properties, Gilbert is now worth more than $41 billion.

That makes the 58-year old tycoon the 17th wealthiest man in the U.S. and the second richest owner of an NBA team. Forbes had previously valued Gilbert's share in Rocket Companies at $4.1 billion. Rocket is worth around $40 billion, more than the Bank of New York Mellon Corp or Ford Motor Co. He owns an estimated 72 percent of the firm.

Quicken Loans is the foundation of Gilbert's fortune. It is the biggest retail mortgage originator in the U.S., underwriting approximately $145 billion last year. That catapulted the company to earn $892 million net income in 2019.

Rocket, which operates Quicken Loans and Rocket Mortgage, settled at $21.51 in New York trading Thursday. The company sold off 100 million shares for $18 each on Wednesday after earlier marketing 150 million of them for $20 to $22 each.

Rocket's offering was led by Morgan Stanley, Goldman Sachs Group Inc., JPMorgan Chase & Co., Credit Suisse Group AG, and Royal Bank of Canada. The shares are trading on the New York Stock Exchange under the symbol RKT.