Aon headquaters in Chicago. (AP)

By Bruce Japsen and Becky Yerak | After talking for a “reasonably long period of time,” Aon Corp. is taking over Hewitt Associates for $4.9 billion in cash and stock to expand its offerings to global employers navigating the complexities of health care reform and employee benefits.

The announcement Monday has pushed stock in the stock in the Chicago-based insurance brokerage and consulting firm  down 7 percent in in late-afternoon trading. Get the full story »