The Journal Register Co., owner of 20 daily newspapers, filed today for bankruptcy protection from its creditors. The Yardley-based company blamed a slump in advertising.

The company operates primarily in the Philadelphia and Cleveland areas, as well as throughout Michigan. Its newspapers include the Delaware County Times and the Trentonian near Philadelphia.

The company would cancel its stock and become a closely held company, owned by its lenders under a proposed reorganization plan filed in U.S. Bankruptcy Court in New York. It listed debt of as much as $1 billion and assets of between $100 million and $500 million in Chapter 11 documents.

"With the increased competition from other forms of media and slumping advertising revenues, the downward pressure on newspaper earnings will likely remain intense in the near term," company chief executive officer James Hall said in court papers.

Since 2006, the company's revenue has dropped by more than 20 percent, Hall said.

In the fall of 2007, the company started cutting costs by selling its corporate jet, eliminating management bonuses and country club memberships, closing 34 publications and cutting at least 112 workers.

Under a proposal filed as part of the bankruptcy case, the company has asked for permission to pay as much as $1.7 million in bonuses to 30 top officers and key employees, should the Journal Register meet certain reorganization goals, including closing more papers and eliminating more employees. Those officers have already been paid $450,000 for a previous round of cuts, according to court papers.

The Journal Register employs about 3,500 people and also owns 159 non-daily newspapers.