A solid embolic material that is capable of filling irregularly shaped and asymmetrical vascular defects in a controlled and predictable manner, without the difficulties associated with delivery of the embolic material through a microcatheter and containment of the embolic material in a defect. A detachable embolic balloon with optional check valve for maintaining liquid in the balloon prior to curing and optional multi-leaflet covering to prevent the balloon from expanding into the native vascular lumen.