Billionaire Leon Cooperman had a few last stock ideas to share on CNBC's Halftime Report on Tuesday. : Billionaire Leon Cooperman had a few last stock ideas to share on CNBC's Halftime Report on Tuesday before he closes his hedge-fund to outside investors at the end of the year. Cooperman shared six of his best ideas in the interview, explaining a few reasons why he thinks the stocks — AMC Networks, Citigroup, CVS Health, Keane, Nabors and United Continental — are a good value for investors.