GenSpring Family Offices L.L.C. has agreed to acquire Cymric Family Office Services.

GenSpring, Palm Beach, Fla., a unit of SunTrust Banks Inc., Atlanta, is not saying how much it will be paying for Cymric, Costa Mesa, Calif., but says it hopes to complete the acquisition by Dec. 31.

Cymric was founded in 1987 by Patricia Soldano, who is the firm’s president.

GenSpring and Cymric together would have a total of $17 billion in assets under advisement, GenSpring says.