Facebook's (NASDAQ: FB) core business is thriving, with strong engagement for the company's namesake social network and its Instagram subsidiary driving impressive top- and bottom-line growth. Here's a look at how the momentum from the company's social networks translated to earnings performance last quarter: Data source: Facebook.With Facebook having since passed 2 billion monthly active users and management indicating that ad placement on the social network is near a saturation point, growth could be more difficult to deliver going forward, but the company is hardly resting on its laurels.