Thanks SDesigns; the GREP feature in particular looks like it might work, assuming I can get the data to merge with a separator between each company. That's where I'm having trouble now; I can't seem to be able to merge a particular column from the CSV that has the company names into a paragraph of text within my document, as it only seems to let me merge in the first company name only. Do you know how I can achieve this, and additionally how I can get it to automatically insert any particular separator (as there are hundreds if not thousands of company names, manually typing in the separator could get very tedious)? Attached is a screenshot of what the final text looks like in the document, though it doesn't seem to let me "Update source" on the paragraph, which would make things much easier.Thank you very much for your time and help!
It sounds like you don't need data merge at all. Just use "File > Place" to get the data into ID, which should insert as tab-deliminated text. Then find-and-replace "^p" (if each company is separated by a paragraph break, or "^t" if it is tabbed) with " •^S" and you're set to apply the nested style. The "^S" after the bullet is a non-breaking space, which you can use to trigger the nested style.