ACQUISITIONS AND DISPOSITIONS - Purchase Price Allocation - One Communications (Details) - USD ($) $ in Thousands		9 Months Ended
May 03, 2016	Sep. 30, 2016
Purchase price allocation:
Gain on One Communications bargain purchase		$ 7,304
One Communications (formerly KeyTech)
Consideration Transferred
Cash consideration	$ 34,518
Total value to allocate
Non-controlling interests	32,909
Business Combination Total Value Allocation	67,427
Purchase price allocation:
Cash	8,185
Accounts receivable	6,451
Other current assets	3,241
Property, plant and equipment	100,892
Identifiable intangible assets	10,590
Other long term assets	3,464
Accounts payable and accrued liabilities	(16,051)
Advance payments and deposits	(6,683)
Current debt	(6,429)
Long-term debt	(28,929)
Net assets acquired	74,731
Gain on One Communications bargain purchase	$ 7,304
One Communications (formerly KeyTech) \| Telecommunication Equipment
Purchase price allocation BDC:
Discounted rate used for cash flows	15.00%
BDC
Consideration Transferred
Cash consideration	$ 7,045
Total value to allocate
Business Combination Total Value Allocation	7,045
Purchase price allocation:
Carrying value of BDC non-controlling interest acquired	2,940
Purchase price allocation BDC:
Excess of purchase price paid over carrying value of non-controlling interest acquired	4,105
One Communications (formerly Keytech) and BDC
Consideration Transferred
Cash consideration	41,563
Total value to allocate
Business Combination Total Value Allocation	$ 74,472
Minimum \| One Communications (formerly KeyTech) \| Income Approach
Purchase price allocation BDC:
Discounted rate used for fair value of noncontrolling interests	15.00%
Minimum \| One Communications (formerly KeyTech) \| Telecommunication Equipment
Purchase price allocation BDC:
Useful life	3 years
Minimum \| One Communications (formerly KeyTech) \| Customer relationships
Purchase price allocation BDC:
Useful life	9 years
Maximum \| One Communications (formerly KeyTech) \| Telecommunication Equipment
Purchase price allocation BDC:
Useful life	18 years
Maximum \| One Communications (formerly KeyTech) \| Customer relationships
Purchase price allocation BDC:
Useful life	12 years

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