The disclosures, which the Fed had resisted, offer the most detailed portrait of a panicky period in which the Fed lent money to banks, brokers, businesses and investors to keep the financial system functioning.

The documents show that some of the biggest names in American business were either coming to the Fed in need of a bailout, or trying to make money at a time when the Fed was trying to entice investors back into the markets. Among the latter were prominent investors and entrepreneurs like John A. Paulson and Michael S. Dell, and the pension funds of the Philadelphia Teamsters and Omaha’s teachers, who were betting they could profit if the rescue worked.

At its peak at the end of 2008, the Fed had about $1.5 trillion in outstanding credit on its books. The central bank, in essence, pumped liquidity, the lifeblood of credit markets, into the circulatory system of an economy that was experiencing a potentially fatal heart attack.

“I think our actions prevented an even more disastrous outcome,” said Donald L. Kohn, who was the Fed’s vice chairman during the crisis. Without the Fed’s help, he said, “liquidity would have dried up even more than it did, asset prices would have fallen even more than they did, and economic activity and employment would have fallen further and faster then they did.”

But Senator Bernard Sanders, independent of Vermont, who wrote a provision in the law requiring the disclosures by Dec. 1, reached a different conclusion.