GOODWILL AND INTANGIBLE ASSETS - Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended	24 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Changes in the carrying amounts of goodwill		$ 0
Balance at the beginning of the period	$ 45,077
Acquisitions	26,986
Deconsolidation of Subsidiary	(1,698)
Impairment charge	(7,491)
Goodwill, Gross	70,364
Accumulated impairment	(7,491)
Balance at the end of the period	62,873	45,077
U.S. Telecom
Goodwill [Roll Forward]
Balance at the beginning of the period	39,639
Acquisitions	3,121
Impairment charge	(7,491)
Goodwill, Gross	42,759
Accumulated impairment	(7,491)
Balance at the end of the period	35,268	39,639
International Telecom
Goodwill [Roll Forward]
Balance at the beginning of the period	5,438
Acquisitions	20,586
Deconsolidation of Subsidiary	(1,698)
Goodwill, Gross	24,326
Balance at the end of the period	24,326	$ 5,438
Renewable energy
Goodwill [Roll Forward]
Acquisitions	3,279
Goodwill, Gross	3,279
Balance at the end of the period	$ 3,279