SUBSEQUENT EVENT (Details) - Subsequent event - U.S. Telecom	3 Months Ended
Mar. 31, 2018 item
SUBSEQUENT EVENT
Number of buildout arrangements with exercised option to purchase sites	1
Cell sites within buildout arrangement	100

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration