SPOKANE, Wash. -- Sterling Financial Corporation (NASDAQ: STSA), the Washington-based parent company of Sonoma Bank in Santa Rosa, filed a report with the U.S. Securities and Exchange Commission today describing that its principal operating subsidiary, Sterling Savings Bank, had completed the previously announced acquisition of First Independent Bank in Vancouver, Wash.

As a result of the acquisition, David DePillo has become executive vice president and chief lending officer of Sterling Savings Bank. Steven Hauschild, former executive vice president and chief approval officer, will replace Mr. DePillo in the role of executive vice president and chief credit officer.

Sterling first announced the planned merger with the bank’s operator, First Independent Investment Group, in November 2011. Terms of the acquisition included paying a premium of $8 million on top of the net value of assets and liabilities at the time of closing. Based on the performance of the acquired assets, Sterling agreed to pay an additional premium of up to $17 million over an 18-month period, according to the announcement.

The acquisition of the more than 100-year-old First Independent Bank adds 14 branches in the Southwest Washington and Portland, Ore. areas to Sterling’s 175 throughout Washington, Oregon, Idaho, Montana and California. First Independent had assets nearing $800 million at the time of the announcement.

 Mergers and acquisitions of other banks has become a public part of Sterling’s growth strategy after the Federal Deposit Insurance Corp. and the Washington Department of Financial institutions mandated that the bank improve its capital position in 2009. That order was lifted in Sept. 2010 after a $730 million recapitalization effort.

The bank reported four quarters of earnings growth in 2011, with net income available to common shareholders of $39.1 million for the year. Non-performing assets decreased 55 percent for the same period, and total assets were $9.19 billion at the end of 2011.

“We are pleased that this transaction was completed as planned and welcome the First Independent customers and employees to Sterling,” said Greg Seibly, CEO, in a release filed with the SEC.

Sterling acquired Northern Empire Bancshares, the former parent company of what was once Sonoma National Bank, in 2007. The move expanded the company’s presence to Northern California, and the bank has since continued operations locally as Sonoma Bank.