Ameriprise Financial has put the finishing touches on its nearly $1 billion purchase of Bank of America’s long-term asset management business Columbia Management. The original agreement dates back to last September.

According to the firm, the Columbia acquisition will add approximately $189 billion to the Minneapolis-based company; bringing U.S. Ameriprise Financial’s total owned, managed and administered assets to $652 billion.

“The Columbia Management acquisition transforms our asset management capabilities and provides a platform to accelerate our growth,” said Jim Cracchiolo, chairman and CEO of Ameriprise Financial. “It enhances our scale, broadens our distribution and strengthens and diversifies our lineup of strong performing retail and institutional funds.”

Ameriprise also said the transaction includes a five-year strategic distribution agreement to BofA’s affiliates, including New York-based U.S. Trust.

Alternately, the financial services firm will combine its current U.S. asset management business, RiverSource Investments, with Columbia, but keep the money management division under the Columbia brand, the release said.

Management at the asset management divisions will continue to the same. William Truscott will lead U.S. asset management, Michael Jones will head Columbia as president and, Colin Moore will hold onto his CIO role. Both Jones and Moore will report to Truscott, the statement said.

While management will remain unscathed, news outlets reported last month that widespread layoffs and departures are expected to come from the Columbia’s fixed-income division. Personnel changes are slated to intensify in September when the transition reaches its final stages.

However, Ben Pratt, Ameriprise VP of public communications, said in email to IMW that this “was not the case.”

“While combinations like this always result in some job rationalizing, the impact here has been relatively small,” Pratt explained. “Just as important, the vast majority of personnel decisions have been made and communicated. There are not significant additional changes to come.”

A detailed determination of the staffing changes was not available, however.