In Georgia, "insurance contracts are governed by the rules of construction applicable to other contracts, and words in the policy must be given their usual and common signification and customary meaning." Northland Ins. Co. v. Am. Home Assur.Co. , 301 Ga.App. 726, 689 S.E.2d 87, 90 (2009) (quoting Turner v. Gateway Ins. Co. , 290 Ga.App. 737, 660 S.E.2d 484 (2008) ). Therefore, the Northland Insurance court interpreted an "Other Insurance" provision by its ordinary meaning without looking at outside sources.