The present invention relates generally to offshore drilling and production operations, and, more particularly, to marine drilling workover/intervention tensioning and compensating devices and methodologies. A heave compensated hydraulic workover device and/or system is provided comprising a hydraulic tensioning cylinder system disposed beneath a rig floor and adapted to be connected at a mandrel to the rig floor through a rotary table disposed in the rig floor. The heave compensated hydraulic workover device and/or system also comprises a well intervention apparatus disposed at least partially within the hydraulic tensioning cylinder system beneath the rig floor, the well intervention apparatus capable of being used in conjunction with at least one of a well, a wellhead, a blow-out pressure system, a jointed tubular, a pipe, and a drilling string. In various aspects, the well intervention apparatus comprises at least one of a hydraulic workover device, a hydraulic jacking system, a coiled tubing apparatus, a wireline device, a slickline device, and an electric line.