.5 billion . on may 17 , 2012 , blackrock increased the maximum aggregate amount to $ 3.785 billion . the cp program is currently supported by the 2012 credit facility . as of december 31 , 2012 and december 31 , 2011 , blackrock had no cp notes outstanding . long-term borrowings the carrying value and fair value of long-term borrowings estimated using market prices at december 31 , 2012 included the following : ( dollar amounts in millions ) maturity amount unamortized discount carrying value fair value .