Click Save 
on the Standard toolbar
(for a new drawing) or File, Save As (for drawing that has been saved
previously).
In the Save As dialog box, select Detached Drawing (*.slddrw) for Save as type.
Specify the file name, then click Save.
Detached drawings are designed so you can open and work in drawing files without the model files being loaded into memory or even being present.
To create a detached drawing:
Click Save on the Standard toolbar
(for a new drawing) or File, Save As (for drawing that has been saved
previously).
In the Save As dialog box, select Detached Drawing (*.slddrw) for Save as type.
Specify the file name, then click Save.
You can save regular drawings as Detached drawings, and vice
versa.
To create a detached drawing template:
Click New
(Standard toolbar), or File,
New.
In the dialog box, click Drawing, then click OK.
Click File, Save As.
In the dialog box, select Detached Drawing (*.slddrw) in Save as type, then click Save.
Click Save As again.
In the dialog box, select Drawing Templates (*.drwdot) in Save as type, then click Save.
Detached drawings cannot be Lightweight drawings.
In the FeatureManager design tree, the icons for Detached drawings display a broken link:
Drawing icon for Detached drawing
Drawing view icon (model view) for Detached drawing with
model not loaded
If the referenced model is needed for an operation within a Detached drawing, you are prompted to load the model file. You can load the model manually by right-clicking a view and selecting Load Model.
When you create a drawing of a large assembly, a dialog box appears asking if you would like to use Detached format for the drawing because of improved performance. You can choose to use Detached format or continue with no change in format.
When a Detached drawing is out of sync with its model, it prints with a watermark that states:
SolidWorks Detached drawing – Out-of-Sync Print
You can send Detached drawings to other SolidWorks users without sending the model files. You also have more control over updating the drawing to the model. Members of the design team can work independently on the drawing, adding details and annotations, while other members edit the model. When the drawing and the model are synchronized, all the details and dimensions added to the drawing update to any geometric or topological changes in the model.
The time required to open a drawing in Detached format is significantly reduced because the model files are not loaded. Because the model data is not loaded into memory, more memory is available to process drawing data, which has significant performance implications for large assembly drawings. You have control over when to load the model, which takes time to load and update the drawing.
The Detached format requires storing more edge data and less surface data. Therefore, some files are larger when converted to Detached, while others are smaller. In general, if your drawings have section views, the file size should decrease. If the drawings do not have section views, the file size may increase. File size is directly related to the number of visible edges in the drawing. For example, if your parts have patterns of features with many instances, it is more likely that the file size will increase when converted to Detached format.
Some changes, such as changes to a section line, detail circle, scale, or projection angle, require a view update. When a drawing view requires an update, the view is displayed with a crosshatch pattern.