Hertz finally got Dollar Thrifty. The Park Ridge, New Jersey-based auto rental giant, already the eighth largest franchise in the world, according to the Franchise Times Top 200, just got a lot larger, completing its long-awaited purchase of Dollar Thrifty Automotive Group. The deal is valued at $2.3 billion. Hertz has spent more than two years trying to buy the Oklahoma-based Dollar Thrifty. First, it had to overcome a rival offer from Avis Budget Group, and then Dollar Thrifty shareholders rejected an earlier offer. Hertz then increased its offer to $87.50 a share in cash in August, and then the deal had to overcome government concerns. Last week, Hertz announced that it had reached a deal with the Federal Trade Commission, clearing the way for the sale. Under the deal, Hertz agreed to sell off its Advantage business along with selected airport locations and other assets.