A unit dose detergent pack includes a pouch and a detergent composition encapsulated within the pouch. The detergent composition includes a surfactant component including an alcohol ethoxy sulfate having a C8-C20 backbone that is ethoxylated with from about 1 to about 10 moles of ethylene oxide and is present in an amount of from about 5 to about 30 weight percent actives, water present in a total amount of from about 5 to about 30 weight percent, and a particular liquid block copolymer present in an amount of at least about 0.5 weight percent actives. The detergent composition has a viscosity of less than about 5,000 cps when diluted with additional water at about a 2:1 weight ratio of the detergent composition:water. The block copolymer is incorporated as a rheology modifying agent.