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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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LONG-TERM DEBT (Details) - USD ($) $ in Thousands			12 Months Ended
LONG-TERM DEBT (Details) - USD ($) $ in Thousands	Jul. 01, 2016	May 03, 2016	Dec. 31, 2016	Dec. 19, 2016	Jan. 11, 2016	Jan. 10, 2016	Dec. 24, 2014	Dec. 19, 2014
Amended Credit Facility
Long-term debt
Maximum borrowing capacity					$ 400,000	$ 275,000
Revolving credit facility \| Amended Credit Facility
Long-term debt
Maximum borrowing capacity					200,000			$ 225,000
Revolving credit facility \| Amended Credit Facility \| Minimum
Long-term debt
Commitment fee (as a percent)			0.175%
Revolving credit facility \| Amended Credit Facility \| Minimum \| LIBOR
Long-term debt
Basis spread on variable rate (as a percent)			1.50%
Revolving credit facility \| Amended Credit Facility \| Minimum \| Base rate
Long-term debt
Basis spread on variable rate (as a percent)			0.50%
Revolving credit facility \| Amended Credit Facility \| Maximum
Long-term debt
Commitment fee (as a percent)			0.25%
Revolving credit facility \| Amended Credit Facility \| Maximum \| LIBOR
Long-term debt
Basis spread on variable rate (as a percent)			1.75%
Revolving credit facility \| Amended Credit Facility \| Maximum \| Base rate
Long-term debt
Basis spread on variable rate (as a percent)			0.75%
Letter of credit sub-facility
Long-term debt
Borrowings			$ 0
Outstanding letters of credit			10,600
Letter of credit sub-facility \| Amended Credit Facility
Long-term debt
Maximum borrowing capacity								10,000
Letter of credit sub-facility \| Amended Credit Facility \| Wholesale Mobility Funds
Long-term debt
Maximum borrowing capacity								25,000
Letter of credit sub-facility \| Credit facility
Long-term debt
Borrowings			$ 0
Swingline sub-facility \| Amended Credit Facility
Long-term debt
Maximum borrowing capacity								$ 10,000
Swingline sub-facility \| Amended Credit Facility \| Federal Funds Effective Rate
Long-term debt
Basis spread on variable rate (as a percent)			0.50%
Swingline sub-facility \| Amended Credit Facility \| Minimum \| Base rate
Long-term debt
Basis spread on variable rate (as a percent)			1.00%
Ahana Debt
Long-term debt
Outstanding debt			$ 2,500
Ahana Debt \| Series A Notes
Long-term debt
Secured debt principal amount				$ 20,600
Stated interest rate				4.427%
Ahana Debt \| Series B Notes
Long-term debt
Secured debt principal amount				$ 45,200
Effective interest rate (as a percent)				5.327%
Ahana Debt \| Series A and Series B Notes
Long-term debt
Outstanding debt			$ 65,800
Ahana Debt \| Term loans
Long-term debt
Term loan assumed							$ 38,900
Ahana Debt \| Term loans \| Minimum
Long-term debt
Effective interest rate (as a percent)			4.50%
Ahana Debt \| Term loans \| Maximum
Long-term debt
Effective interest rate (as a percent)			6.00%
PSE&G \| Term loans
Long-term debt
Stated interest rate			11.30%
One Communications (formerly KeyTech)
Long-term debt
Cash consideration		$ 34,518
One Communications (formerly KeyTech) \| Minimum
Long-term debt
Potential cash dividend					13,000
One Communications (formerly KeyTech) \| Amended Credit Facility
Long-term debt
Secured debt principal amount					$ 60,000
One Communications (formerly KeyTech) \| Term loans
Long-term debt
Term loan assumed		$ 35,400
Outstanding debt			$ 32,100
One Communications (formerly KeyTech) \| Term loans \| Three month LIBOR
Long-term debt
Basis spread on variable rate (as a percent)		3.25%
Description of variable rate basis		three-month LIBOR
Innovative \| Term loans
Long-term debt
Secured debt principal amount	$ 60,000
Stated interest rate	4.00%
Outstanding debt			60,000
Finance costs to lock in rate	$ 900
Deferred finance costs, net			$ 800
Cash consideration	$ 51,000