Stocks fell modestly Wednesday on investor concerns about Greece's debt situation, a stronger U.S. dollar, and Federal Reserve (Fed) Chairman Ben Bernanke's outline for eventually removing some of the trillions of dollars used to support the U.S. financial system. Stocks rose Tuesday on growing bets that the European Union will rescue Greece from its debt problems, but stocks were volatile Wednesday on worries that Greece is only the first of many countries being pressured by growing budget deficits. In Washington, Bernanke said that while the U.S. economy continues to require the support of emergency programs the central bank enacted at the height of the financial crisis, “at some point the Federal Reserve will need to tighten financial conditions.” He said the Fed would remove cash from the system before it boosts interest rates, and that its decision to raise the emergency discount rate is not the same as a shift in policy. In economic news, the U.S. trade deficit widened unexpectedly in December to $40.2 billion, the government reported, reflecting an increase in imports as the economy improves. The U.S. dollar rose versus the euro and the yen. Light sweet crude oil for March delivery rose 77 cents to $74.52 a barrel on the New York Mercantile Exchange. Gold for April delivery fell 90 cents to $1,076.30 an ounce. The Dow Jones industrial average fell 20.26, or 0.2 percent, to 10,038.38. Walt Disney reported higher-than-expected quarterly profit and revenue, but shares of the entertainment giant fell 1 percent. The broader Standard & Poor's 500 index fell 2.39, or 0.2 percent, to 1,068.13. The technology-heavy Nasdaq composite index fell 3.00, or 0.1 percent, to 2,147.87. The New York Stock Exchange composite index fell 16.04 to 6,819.12. The American Stock Exchange composite index fell 7.14 to 1,786.23. And the Russell 2000 index rose 0.65 to 595.82.