Private equity firms Leonard Green & Partners and Ares Management LLC will purchase CHG Healthcare Services for an undisclosed amount.

Salt Lake City-based CHG, which provides healthcare staffing in the U.S., is majority owned by funds affiliated with J.W. Childs Associates LP, a Waltham, Mass.-based private equity firm.

Leonard Green, based in Los Angeles, has raised more than $15 billion in capital since it was started in 1989. The firm has invested in 62 companies, including David’s Bridal, Aspen Dental Management Inc. and Prospect Medical Holdings Inc.

Leonard Green owns a minority stake in David's Bridal after it sold the retailer to Clayton Dubilier & Rice in October. 

Ares Management, also headquartered in Los Angeles, has invested in Jacuzzi Brands Corp., Stream Global Services Inc. and Nortek Inc.