The priority of calls generated from this call details entry. The priority determines whether calls can be bumped
for higher priority calls. The value of priority falls into ranges:
0-19 - call bumped by incoming or outgoing, voice or data calls
20-39 - call bumped by outgoing voice and incoming or outgoing data calls
40-59 - call bumped by emergency voice calls or incoming or outgoing data calls
60-99 - call bumped by emergency voice calls or outgoing data calls.
Note that when the call is bumped by a data call, the data call must have higher
priority than the call being bumped.