Hi Sandeep.
Detail list that contains document data only exist in ERP side (managed system side), so SolMan does not have its information.
In case of Business Process Monitoring, SolMan only has measured value and alert rating. So alert cube in SolMan does not have document information.
Also in case of Business Process Analytics, it also aggregated measured value. So its cube also does not contains detail document information.
So in standard, only detail document information is available in ECC side.
If you really want to get document information without accessing ECC detail list, the possible workaround is, by using notification Badi, access ERP detail list, and include required information in the e-mail. This requires some development in solman notification badi and also ERP side (function module to extract detail list that will be called within Badi).
Best Regards
Keiji