1. A position detection device comprising: a detecting section that detects an indicator separable from a user's hand and a target different from the indicator, the indicator performing a first operation with respect to an operation surface, the target performing a second operation with respect to the operation surface; an imaging section that forms a captured image obtained by imaging a range including the operation surface; and a control section that detects a motion of the target with respect to the operation surface and a position of the indicator with respect to the operation surface based on the captured image to determine whether to detect the first operation performed by the indicator as an input or to negate the indicator and to instead detect the second operation performed by the target as the input, wherein the control section determines whether or not to detect the position of the indicator or the motion of the indicator as the input based on a distance between the indicator and the operation surface and a distance between the target and the operation surface, and wherein the control section determines that the position or motion of the indicator is not to be detected as the input when the distance between the indicator and the operation surface is longer than the distance between the target and the operation surface.