SPOKANE, Wash. (AP) - The parent company of Sterling Savings Bank is laying off 6 percent of its employees in an effort to cut costs.

In a filing with the Securities and Exchange Commission, Sterling Financial Corp. said it expected to complete the 150-job reduction in the first three months of 2012. The move is projected to save $15 million a year, and will cost $3 million in severance pay.

Chief Executive Officer Greg Seibly says the challenging interest rate environment and uncertain economic outlook led to the cuts.

Sterling spokeswoman Cara Coon says the layoffs affected many divisions with the exception of positions such as customer service.

Sterling Savings Bank has 2,500 employees and operates 175 branches in Washington, Oregon, Idaho, California and Montana.

The bank is changing its name to Sterling Bank in a $3.5 million rebranding.

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