Joan Tisch, a billionaire matriarch of the family that co-founded Loews Corp. and co-owns the New York Giants football team, has died. She was 90.

She died Thursday after a brief illness, according to the Giants website. No cause was given.

With a net worth of $4.5 billion, according to the Bloomberg Billionaires Index, Tisch was one of America's richest women. The 2005 death of her husband, Robert, and the 2003 death of his brother and business partner, Laurence, left her and her sister-in-law overseeing a multibillion-dollar fortune.
- Bloomberg News