I am a long-time TurboTax user and want to review the details around my cash donations from a past tax return, but can not find the detail or form where this is listed.

The PDF download for a prior year tax return will have you donations to a charity listed on the Charitable Organization Worksheet for the particular charity.

To access your prior year online tax returns sign onto the TurboTax website with the userID you used to create the account - https://myturbotax.intuit.com/

Scroll down and on the section Your tax returns & documents click on Show.  Click on the Year and Click on Download/print return (PDF)