Javascript error in Apex while navigating the page to different url oracle apex

Question

I have grid column and that should get the page url and redirect to that page which i click that column name, but i am getting JS error and its not moving to another page from the URL the link taken as below

Js code in grid column

javascript:var x=window.open( '&DOCUMENT_URL.' , '_blank' )

Url which is taking automatically:

https://devords.bluqube.co.uk/devmain1/atob('Zj9wPTIwMDoyNDAxOjgzMTM3NDc3NTUyMTk6QVBFWF9DTE9ORV9TRVNTSU9OOjoyNDAxOlAyNDAxX0RPQ1VNRU5UX0lELFAyNDAxX0xFREdFUl9UWVBFOjEzMTc2NzgsUyZjcz0zWXBWUGZKOVN6YzBZaENVX254aWRDTmRTcDFkaUhoaXkyYy16bjRFckNTX2ZySkx3dVlzLXhhZ0hFUUx6bUhkY3RPMmF5ZkE5SXoxdWFRNEItQTNnWUE=')

Can anyone help

I am expecting the when i click the column name it has to redirect correclty , i have mentioned the url in grid select query for that column but why its taking the below link

https://devords.bluqube.co.uk/devmain1/atob('Zj9wPTIwMDoyNDAxOjgzMTM3NDc3NTUyMTk6QVBFWF9DTE9ORV9TRVNTSU9OOjoyNDAxOlAyNDAxX0RPQ1VNRU5UX0lELFAyNDAxX0xFREdFUl9UWVBFOjEzMTc2NzgsUyZjcz0zWXBWUGZKOVN6YzBZaENVX254aWRDTmRTcDFkaUhoaXkyYy16bjRFckNTX2ZySkx3dVlzLXhhZ0hFUUx6bUhkY3RPMmF5ZkE5SXoxdWFRNEItQTNnWUE=')