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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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

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Fair value amount of debt instrument that was repurchased.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

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The cash inflow from the issuance of long-term tax exempt debt that is not secured by collateral.

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Long-Term Debt and Capital Leases - Additional Information (Detail) $ in Thousands	8 Months Ended	12 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) $ / NotesPayable	Apr. 30, 2013 USD ($)	Apr. 30, 2014 USD ($)
Debt Instrument [Line Items]
Aggregate principal amount	$ 535,711	$ 523,647		$ 508,019
Loss on debt extinguishment	0	999	$ 15,584
Carrying value of revolver debt		$ 57,422
Maine Bonds [Member]
Debt Instrument [Line Items]
Maturity date		Jan. 01, 2025
Debt instrument interest rate		6.25%
Aggregate principal amount		$ 21,400
Maine Bonds [Member] \| Variable Rate Bonds [Member]
Debt Instrument [Line Items]
Carrying value of bonds		$ 3,600
Senior Subordinated Notes Due 2019 Notes [Member]
Debt Instrument [Line Items]
Maturity date		Feb. 15, 2019
Debt instrument interest rate		7.75%
Issued discount	1,319	$ 1,372		1,491
Aggregate principal amount	323,681	368,928		323,509
Carrying value of bonds		370,300
Aggregate principal repurchase amount		$ 14,700
Repurchase price per debt instrument \| $ / NotesPayable		101.0
Loss on debt extinguishment		$ 478
Senior Secured Asset Based Revolving Credit Facility, Due 2020 [Member]
Debt Instrument [Line Items]
Maturity date		Feb. 26, 2020
Revolving credit facility		$ 190,000
Additional increase in credit facility		$ 100,000
Line of credit facility interest rate description		One month LIBOR plus between 1.75% and 2.50%
Debt instrument stated percentage		2.25%
Maturity date description		The ABL Facility matures on February 26, 2020. If we fail to refinance the 2019 Notes on or before November 16, 2018, the maturity date for the ABL Facility will be November 16, 2018.
Borrowing base		$ 148,473
Available revolving credit facility		64,112
Aggregate principal amount		57,422
Outstanding irrevocable letters of credit totaling		$ 26,939
Senior Secured Asset Based Revolving Credit Facility, Due 2020 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument stated percentage		1.75%
Senior Secured Asset Based Revolving Credit Facility, Due 2020 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument stated percentage		2.50%
Senior Secured Revolving Credit Facility, Due 2016 [Member]
Debt Instrument [Line Items]
Maturity date		Mar. 18, 2016
Debt instrument stated percentage		3.75%
Aggregate principal amount	131,300			$ 133,860
Senior Secured Revolving Credit Facility, Due 2016 [Member] \| Write off Deferred Financing Costs [Member]
Debt Instrument [Line Items]
Loss on debt extinguishment		$ 521
New York Bonds [Member]
Debt Instrument [Line Items]
Maturity date		Dec. 01, 2044
Debt instrument interest rate		3.75%
Carrying value of bonds	25,000	$ 25,000
Additional bond issued		$ 15,000
Revenue Bonds Series 2015 Due August 2035 [Member]
Debt Instrument [Line Items]
Maturity date		Aug. 01, 2035
Debt instrument interest rate		5.125%
Aggregate principal amount		$ 15,000
Carrying value of bonds		15,000
Additional bond issued		15,000
Fixed Rate Bonds [Member]
Debt Instrument [Line Items]
Carrying value of bonds		458,700
Fair value of fixed rate debt		$ 458,775
Fixed Rate Bonds [Member] \| Vermont Bonds [Member]
Debt Instrument [Line Items]
Maturity date		Apr. 01, 2036
Debt instrument interest rate		4.75%
Carrying value of bonds		$ 16,000
New Hampshire Bonds [Member]
Debt Instrument [Line Items]
Maturity date		Apr. 01, 2029
Debt instrument interest rate		4.00%
Aggregate principal amount	5,500
Carrying value of bonds	11,000	$ 11,000
Additional bond issued	$ 5,500
Second Lien Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate			11.00%
Loss on debt extinguishment			$ 15,584
Second Lien Notes [Member] \| Write off Deferred Financing Costs [Member]
Debt Instrument [Line Items]
Loss on debt extinguishment			2,767
Second Lien Notes [Member] \| Write off Unamortized Original Issue Discount [Member]
Debt Instrument [Line Items]
Loss on debt extinguishment			2,074
Second Lien Notes [Member] \| Tender Premium and Tender Fees [Member]
Debt Instrument [Line Items]
Loss on debt extinguishment			$ 10,743
Subsequent Issuance of Senior Subordinated Notes [Member] \| Senior Subordinated Notes Due 2019 Notes [Member]
Debt Instrument [Line Items]
Issuance of senior subordinated notes, face amount		60,000
Issued discount		476
Original Issuance of Senior Subordinated Notes [Member] \| Senior Subordinated Notes Due 2019 Notes [Member]
Debt Instrument [Line Items]
Issuance of senior subordinated notes, face amount		$ 325,000