Anyone know what this is "18C02B23" instead of a phone number i see this in "Detailed Extension Call Detail Report"

Detailed Extension Call Detail Report Date: 10/26/2017
Extension : 188191 Name: ()

hh:mm:ss Call Type Called To Called From
Account Code Queue
Number Name Nickname Number Name Nickname Location
8:59:09 8:59:55 0:00:46 outgoing 480410xxxx
8:37:21 8:37:35 0:00:14 outgoing 18C02B23
9:03:47 9:04:40 0:00:53 outgoing 18C02B23
9:07:04 9:07:44 0:00:40 outgoing 18C02B23
9:11:02 9:11:43 0:00:41 outgoing 18C02B23
9:26:57 9:30:26 0:03:29 outgoing 18C02B23
9:34:03 9:35:14 0:01:11 outgoing 18C02B23
9:38:26 9:38:37 0:00:11 outgoing 480483xxxx

Equipment Type: CIX670 : B--U Equipment Type: CIX40A2 : GCTU2