Very large file although images unembedded

If you an open the original

Unembed all the images

Then setup a new document with the same page size and margins

With the old document open go to the Pages Panel and select all the pages in the document

Use the submenu for that panel and choose Move Pages

You can then select the new document as the target document

Move all the pages to the new document.

Then try save it - as it's a new document.

2 other things to try

Save as an InDesign Template - when you open it it will open as untitled

Or try save as IDML and see if that opens.

Just extra things to try.

Often is content of deleted assets in the file, liker former embedded images.

To solve the problem I do following:

1. Read the important parameters of the file in document setup and the settings of the baseline gird.
2. Create a new document with 2 pages based on the settings of step 1. 
3. The new document must not have any styles except those inherit in a new document in […], no swatches
4. Have both document saved and open
5. Go to the old document, > Layout > Pages > Move, select all pages, destination is the new document at the start
6. Delete the intioal 2 pages and save the new document. 

The file size should now be reasonable small.

Hi @Lavitas Macutis , There is a known bug with Photoshop files saving ancestor metadata, and bringing the excess metadata into InDesign. The Photoshop bloat can be fixed via scripting. More in this thread:

https://community.adobe.com/t5/indesign-discussions/is-there-a-script-to-clear-indesign-metadata-redundancy-or-the-clipboard-just-like-photoshop/m-p/12638735#M460299

Have you done a Save-As under a new name (which purges Undo and other "back room" data) or exported it again to IDML? Either one should purge any excess baggage.

If it's still large, it may just be a large document; if it seems out of proportion after those two steps, provide a few more details about page count etc.