RETIREMENT PLANS (Details) - Pension plans for GT&T employees - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Retirement plans
Employment period or credited service period for which participants' average salary or hourly wages is used as a base to calculate benefits	3 years
Weighted-average rates assumed in the actuarial calculations for the pension plan
Discount rate (as a percent)				5.75%	5.75%	5.75%
Annual salary increase (as a percent)				6.50%	6.50%	7.50%
Expected long-term return on plan assets (as a percent)	6.50%	7.00%	7.00%
Projected benefit obligations:
Balance at beginning of year	$ 14,093,000	$ 12,237,000
Service cost	652,000	612,000	$ 543,000
Interest cost	766,000	720,000	665,000
Benefits and settlements paid	(1,329,000)	(623,000)
Actuarial gain	218,000	1,129,000
Exchange rate adjustment		18,000
Balance at end of year	14,400,000	14,093,000	12,237,000
Plan net assets:
Balance at beginning of year	13,165,000	12,673,000
Actual return on plan assets	110,000	267,000
Company contributions		832,000
Benefits and settlements paid	(1,329,000)	(623,000)
Exchange rate adjustment		16,000
Balance at end of year	11,946,000	13,165,000	12,673,000
Funded status of plan
Under funded status of plan				$ (2,454,000)	$ (928,000)
Pension plan assets
Fair value of plan assets	13,165,000	12,673,000	12,673,000	$ 11,946,000	$ 13,165,000	$ 12,673,000
Weighted-average asset allocations (as a percent)				100.00%	100.00%
Amounts recognized on the consolidated balance sheets
Other Liabilities				$ 2,454,000	$ 928,000
Accumulated other comprehensive loss, net of tax				(3,481,000)	(2,672,000)
Amounts recognized in accumulated other comprehensive loss
Net actuarial loss				(5,836,000)	(3,148,000)
Accumulated Other Comprehensive Income (Loss), before Tax, Total				(5,836,000)	(3,148,000)
Accumulated other comprehensive loss, net of tax				(3,481,000)	$ (2,672,000)
Components of the plan's net periodic pension cost
Service cost	652,000	612,000	543,000
Interest cost	766,000	720,000	665,000
Expected return on plan assets	(813,000)	(848,000)	(949,000)
Amortization of unrecognized net actuarial loss	245,000	218,000	150,000
Net periodic pension cost	850,000	$ 702,000	$ 409,000
Additional disclosure
Expected contribution in 2016	$ 586
Estimated Pension Benefits
2016				643,000
2017				667,000
2018				757,000
2019				614,000
2020				800,000
2021-2025				5,286,000
Total				8,767,000
Minimum
Funded status of plan
Percentage of plan assets to be invested within Guyana	70.00%
Maximum
Funded status of plan
Percentage of plan assets to be invested within Guyana	80.00%
Level 1
Plan net assets:
Balance at end of year	$ 10,166,000
Pension plan assets
Fair value of plan assets	10,166,000			10,166,000
Level 2
Plan net assets:
Balance at end of year	1,780,000
Pension plan assets
Fair value of plan assets	1,780,000			1,780,000
Cash, cash equivalents, money markets and other
Plan net assets:
Balance at end of year	9,730,000
Pension plan assets
Fair value of plan assets	9,730,000			$ 9,730,000
Weighted-average asset allocations (as a percent)				81.50%	80.00%
Cash, cash equivalents, money markets and other | Level 1
Plan net assets:
Balance at end of year	7,950,000
Pension plan assets
Fair value of plan assets	7,950,000			$ 7,950,000
Cash, cash equivalents, money markets and other | Level 2
Plan net assets:
Balance at end of year	1,780,000
Pension plan assets
Fair value of plan assets	1,780,000			1,780,000
Equity securities
Plan net assets:
Balance at end of year	1,760,000
Pension plan assets
Fair value of plan assets	1,760,000			$ 1,760,000
Weighted-average asset allocations (as a percent)				14.70%	13.00%
Equity securities | Level 1
Plan net assets:
Balance at end of year	1,760,000
Pension plan assets
Fair value of plan assets	1,760,000			$ 1,760,000
Fixed income securities
Plan net assets:
Balance at end of year	456,000
Pension plan assets
Fair value of plan assets	456,000			$ 456,000
Weighted-average asset allocations (as a percent)				3.80%	7.00%
Fixed income securities | Level 1
Plan net assets:
Balance at end of year	456,000
Pension plan assets
Fair value of plan assets	$ 456,000			$ 456,000