PR Card document number

[Canadiandreaming]

Hi,

Could somebody please tell me which is the "document number" that I enter for checking-in to a flight? There is the ID number on the front, and then a number top right on the back.

Thank you

 

[Canadiandreaming]

Anybody?

My PR card has an ID number on the front but then another number, beginning PB, on the back. The airline wants me to enter the "document number". Which one is it please?