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FAIR VALUE OF FINANCIAL INSTRUMENTS - Additional Information (Detail) - USD ($)	Apr. 30, 2018	Mar. 31, 2018
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

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611

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- Definition

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