Regulators closed four banks in the United States on Friday, including one in Colorado with over $1 billion in assets, bringing the total number of closures this year to 84.

The largest of the failed banks, the Community Banks of Colorado, had $1.38 billion in assets and $1.33 billion in total deposits as of June 30, the Federal Deposit Insurance Corp said. It is the largest bank to fail since August 19, 2011.

Bank Midwest, NA, Kansas City, Mo., agreed to assume all the deposits of Greenwood-based Community Banks of Colorado and to purchase essentially all of he assets. Its 40 branches will reopen on Saturday as branches of Bank Midwest.

The Federal Reserve Board, which appointed the FDIC as the receiver of the Colorado-based bank, said it had been critically undercapitalized since July 29.

Among other banks to fail on Friday included two in Georgia and one in Florida.

In Georgia, regulators closed Community Capital Bank in Jonesboro and the Decatur First Bank in Decatur.

State Bank and Trust Co, Macon, Ga., has agreed to assume the deposits and purchase essentially all of the assets of Community Capital Bank, which as of June 30 had $181.2 million in assets. State Bank and Trust Co is a subsidiary of State Bank Financial Corp .

Fidelity Bank, Atlanta, meanwhile, agreed to assume all of the deposits and purchase essentially all of the assets of Decatur First Bank. Decatur First Bank had about $191.5 million in assets, and $179.2 million in deposits as of the end of the end of June.

In Florida, regulators shut down the Old Harbor Bank in Clearwater, and entered into an agreement with 1st United Bank of Boca Raton to assume the bank's deposits and purchase almost all of the assets. Old Bank Harbor had $215.9 million in assets as of June 30 and $217.8 million in total deposits.

Friday's four bank failures cost the FDIC's insurance fund an estimated $358.8 million. The Colorado bank's failure made up the bulk of that cost with and estimated $224.9 million.

Most of the banks that have failed so far this year have had less than $1 billion in assets, illustrating the problems facing small banks.

FDIC officials, however, expect there to be fewer failures this year than in 2010 when 157 banks were closed.

(Reporting by Sarah N. Lynch and Dave Clarke; editing by Carol Bishopric)