This was a quick search and is wide in its scope, but I'm sure more specifics on his departure could be found with minimal googling:
http://www.guardian.co.uk/commentisfree/cifamerica/2011/jun/08/dick-cheney-halliburton-supreme-court
Being a Texan, I DO remember the fiasco about Halliburton buying Dresser which turned out badly. Who else to blame it on but the CEO. Although he received a separation package, he was not seen in good light by those left at Halliburton.