DLP 12.5 local mailbox scanning & outlook webmail

Hi,

I am looking for some confirmation / a potential solution around outlook webmail and potential sensitive data sorted within outlook mailboxes.

If I was to email myself internally within my organisation a list of credit card numbers, for example, and then log in to outlook webmail external to the organisation, would DLP pick up this email?  As it would not have actually left the organisation's permiter.

Does DLP have the capability to scan data within outlook mailnboxes?

Thanks in advance