The Federal Reserve hoped reviving a crisis-era program in May would limit fallout to the United States from Europe's debt debacles.

A document, released Wednesday, provides insights into the Fed's thinking at that time.

To contain the European crisis, the Fed on May 9 agreed to supply European central banks — and the Bank of Japan — with much-in-demand dollars in return for foreign currencies.

Fed officials believed these "swap" arrangements would be helpful in limiting the "adverse implications of recent developments for the U.S. economy," the document says.

Fears about Europe's debt problems, however, have roiled Wall Street.