In July 2007, American business magnate and investor Warren Buffett's holding company Berkshire Hathaway bought an Israeli company, Iscar, its first non-U.S. acquisition, for $4 billion. Since the 1970s, Israel has received military aid from the United States, as well as economic assistance in the form of loan guarantees, which now account for roughly half of Israel's external debt. Israel has one of the lowest external debts in the developed world, and is a net lender in terms of net external debt (the total value of assets vs. liabilities in debt instruments owed abroad), which in December 2015[update] stood at a surplus of US$118 billion.