Yes it is taxable. You are not subject to the 10% early withdrawal penalty since you were older than 59 1/2, but a distribution from a retirement account is taxable. You will receive a 1099R for the money you took out.
To enter your retirement income, Go to Federal> Wages and Income>Retirement Plans and Social Security>IRA 401 k) Pension Plan Withdrawals to enter your 1099R.