I'll just put an abbreviated description on here...
Denver PD ISD channels on the Denver Public Safety EDACS system belong to the Investigative Support Division (ISD) used mainly by DPD’s Special Investigation Bureau’s Fugitive Apprehension Unit who use the "Ida" callsigns. The Lt uses Ida-4 and the Sgt uses Ida-20. The rest of the unit uses numbers in the Ida-2X series. The ISD talk groups are in ProVoice so not monitorable unless you have some software. PM me for channel numbers.