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FAIR VALUE OF FINANCIAL INSTRUMENTS - Additional Information (Detail) - USD ($) | Apr. 30, 2018 | Mar. 31, 2018
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Significant Other Observable Inputs (Level 2) |  |
Debt Instrument [Line Items] |  |
Carrying value of revolver debt |  | $ 52,600,000
Fair Value | Fixed Rate Bonds |  |
Debt Instrument [Line Items] |  |
Fair value of fixed rate debt |  | 108,003,000
Fair Value | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 2.50% | Secured Debt | Significant Other Observable Inputs (Level 2) |  |
Debt Instrument [Line Items] |  |
Fair value of fixed rate debt |  | 345,625,000
Carrying Value | Fixed Rate Bonds |  |
Debt Instrument [Line Items] |  |
Fair value of fixed rate debt |  | 107,000,000
Carrying Value | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 2.50% | Secured Debt |  |
Debt Instrument [Line Items] |  |
Fair value of fixed rate debt |  | $ 347,353,000
Subsequent Event | Finance Authority Of Maine Solid Waste Disposal Revenue Bonds Series 2015R-2 | Unsecured Debt |  |
Debt Instrument [Line Items] |  |
Aggregate principal amount | $ 15,000,000 |

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