GOODWILL AND INTANGIBLE ASSETS - Change In Carrying Amount Of Telecommunications Licenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Telecommunications licenses
Impairment of intangible assets	$ 0	$ 0
Changes in the carrying amount of the company's telecommunications licenses, by operating segment
Balance at the beginning of the period	44,090
Balance at the end of the period	43,468	44,090
Telecommunications Licenses
Telecommunications licenses
Impairment of intangible assets	0	0
Changes in the carrying amount of the company's telecommunications licenses, by operating segment
Balance at the beginning of the period	44,090	39,687
Acquired licenses		5,025
Amortization	(622)	(622)
Balance at the end of the period	43,468	44,090
Telecommunications Licenses | U.S. Wireless
Changes in the carrying amount of the company's telecommunications licenses, by operating segment
Balance at the beginning of the period	24,913	19,888
Acquired licenses		5,025
Balance at the end of the period	24,913	24,913
Telecommunications Licenses | U.S. Wireline
Changes in the carrying amount of the company's telecommunications licenses, by operating segment
Balance at the beginning of the period	31	31
Balance at the end of the period	31	31
Telecommunications Licenses | Island Wireless
Changes in the carrying amount of the company's telecommunications licenses, by operating segment
Balance at the beginning of the period	19,146	19,768
Amortization	(622)	(622)
Balance at the end of the period	$ 18,524	$ 19,146