Insurance   brokerage Aon (AON) unveiled a $4.9 billion cash-and-stock deal on Monday to take over human-resource service company Hewitt Associates (HEW).

The 50% cash and 50% stock deal is worth $50 a share and represents a 41% premium on Hewitt’s closing price Friday. Aon said it will issue $25.61 in cash and 0.6362 share for each Hewitt share.

The companies see the deal closing by mid-November. Aon said it anticipates the acquisition will significantly add to its 2011 cash earnings and to its GAAP EPS in 2012.

To help finance the deal, Aon said it has commitments for a three-year, $1 billion bank term loan and commitments for a $1.5 billion bridge loan facility.

"This agreement reflects our ongoing efforts to ensure that Aon's associates, capabilities and technology remain at the forefront of our industry, providing distinctive client value," Aon CEO Greg Case said in a statement. "As we continue to grow our business, this merger will give us a broader portfolio of innovative products and services focused on what we believe are two of the most important topics in the global economy today – risk and people."

After the deal closes, Aon said it plans to integrate Hewitt with its existing consulting and outsourcing operations as Aon Hewitt. The combined unit will be led by Hewitt CEO Russ Fradin.