When do I record medical expense paid in 2017 but reimbursed from HSA in 2018?

I paid a medical expense with my own credit card in 2017.  I won't receive reimbursement from HSA until 2018.  per Turbotax: "Do not include amounts that will be reimbursed with distributions in a later year".  If I don't include this amount in 2017, when do I record this expense?