The Dow Jones industrial average fell 54 points to 12,913 as of 10:30 a.m. Tuesday. The Standard & Poor's 500 was down five points at 1,401. The Nasdaq composite index fell eight points to 2,968 points.
ConAgra advanced after it agreed to buy Ralcorp for $5 billion, a deal that will make it the nation's biggest maker of private-label foods. Ralcorp surged $18.55 to $88.77. Corning Inc., a specialty glass maker, rose 76 cents to $12.32 after it said that North American television sales are stronger than expected in the fourth quarter, boosting demand for its products.
Investors were unmoved by two reports that suggested that outlook for the U.S. economy may be improving.
Consumer confidence rose this month to the highest level in almost five years, pushed up by steady improvement in hiring. The Conference Board's consumer confidence index rose to 73.7 in November from 73.1 in October. Both are the best readings since February 2008.
The government reported separately that U.S. companies increased their orders of machinery and equipment last month, a sign that business investment is rising. Orders for core capital goods rose 1.7 percent in October, the best showing since a 2.3 percent rise in May.
Stocks advanced in Europe after Greece's euro partners and the International Monetary Fund agreed to release funds the country needs to avoid imminent bankruptcy, as well as introduce a series of measures designed to reduce the country's massive debts to a more manageable level within a decade.
The Stoxx 50 index of leading European shares was up 0.4 percent to 2,542.93
The yield on the 10-year Treasury note was little changed at 1.66 percent.
Among other stocks making big moves:
— Airgas Inc., a specialty supplier of medical and industrial gases, fell $3.15 to $87.32 after disclosing that its chairman sold 1.2 million shares of the company's stock in a privately negotiated block trade.