Kentucky's largest insurer and Louisville's largest health care provider may be headed for a split.Norton Healthcare is threatening to drop Anthem Blue Cross/Blue Shield from its supported insurers if the company doesn't agree to higher reimbursements and other administrative changes.Anthem spokesperson Tony Felts says this is not the time to increase health care costs."Norton is requesting a reimbursement increase of 20% or more precisely at a time when our employer accounts and anthem customers are struggling in the current economic downturn," he says.Norton Associate Vice President of Managed Care Jim Meyers says the extra fees are necessary to provide care, and Norton doesn't want to drop Anthem."Our intent is to get a new contract," he says. "But if it leads to that then I guess that's the way it ends up, but that's not our goal."If Anthem is dropped, its customers would face out of network charges for Norton hospitals and doctors. Felts says the insurer will make exceptions for Kosair Children's Hospital.