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LONG-TERM DEBT - Additional Information (Detail) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) | Mar. 31, 2017 USD ($) interest_rate_derviative | Apr. 30, 2018 USD ($)
Debt Instrument [Line Items] |  |  |
Loss on debt extinguishment | $ 0 | $ 472,000 |
Cash Flow Hedging | Other Current Assets |  |  |
Debt Instrument [Line Items] |  |  |
Derivative asset fair value | 103,000 |  |
Cash Flow Hedging | Other Noncurrent Assets |  |  |
Debt Instrument [Line Items] |  |  |
Derivative asset fair value | $ 953,000 |  |
Cash Flow Hedging | Interest Rate Derivative |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate derivatives entered into | interest_rate_derviative |  | 3 |
Notional amount |  | $ 60,000,000 |
Weighted average percentage rate paid |  | 1.95% |
Cash Flow Hedging | Interest Rate Derivative | LIBOR |  |  |
Debt Instrument [Line Items] |  |  |
Floor interest rate received |  | 1.00% |
Cash Flow Hedging | Interest Rate Derivative - February 2021 |  |  |
Debt Instrument [Line Items] |  |  |
Notional amount |  | $ 35,000,000 |
Cash Flow Hedging | Interest Rate Derivative - February 2022 |  |  |
Debt Instrument [Line Items] |  |  |
Notional amount |  | 25,000 |
Unsecured Debt | VEDA Bonds |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, interest rate during period | 4.625% |  |
Unsecured Debt | Revenue Bonds Series Two Thousand Five Rone Due Two Thousand Twenty Five |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate principal amount |  | 3,600,000 |
Unsecured Debt | Revenue Bonds Series Two Thousand Five Rtwo Due Two Thousand Twenty Five |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate principal amount |  | 21,400,000 |
Unsecured Debt | Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 (FAME Bonds 2005R-3) |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate principal amount |  | $ 25,000,000 |
Debt instrument interest rate percentage |  | 5.25% |
Subsequent Event | Unsecured Debt | Finance Authority Of Maine Solid Waste Disposal Revenue Bonds Series 2015R-2 |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate principal amount |  |  | $ 15,000,000
Debt instrument interest rate percentage |  |  | 4.375%
Subsequent Event | Unsecured Debt | VEDA Bonds |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate principal amount |  |  | $ 16,000,000
Debt instrument interest rate percentage |  |  | 4.75%

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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