BUSINESS DESCRIPTION & SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Business (Details)	Dec. 31, 2021 state mi
Number of fiber route miles \| mi	52,400
Minimum
Number of states \| state	20

The number of states the entity operates in as of the balance sheet date.

No definition available.

Name:	us-gaap_NumberOfStatesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant