So it sounds like it went from a 401K with the company to an IRA with Merrill Lynch.
If so you will get a 1099R that needs to show this. It would not be taxable if it goes from a Traditional 401K to Traditional (non-Roth) IRA.
TurboTax will ask if it rolled over and if it was a Roth. If not, it will not be taxable.
To enter pension and annuity Payments (1099-R)
• Click on Federal Taxes
• Click on Wages and Income
• Click on I'll choose what I work on (if shown)
• Scroll down to Retirement Plans and Social Security
• On IRA, 401(k), Pension Plan Withdrawals (1099-R), click the start or update button