The increase during the period in capital lease obligations due to entering into new capital leases.

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DEBT AND LINES OF CREDIT - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Jan. 31, 2016
Debt Instrument [Line Items]
Non-cash interest expense	$ 2,296,000	$ 2,269,000
Capital lease obligations incurred	500,000
Revolving line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	50,000,000
Remaining borrowing capacity	33,387,707
Line of credit outstanding	9,880,000
Outstanding letters of credit	$ 0
Term Loan Facility Due 2020 [Member] \| Term Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	7.50%
Senior secured notes due 2022 \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	8.75%
San Juan Loan \| Term Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	7.25%
Senior secured notes			$ 125,000,000.0
Interest rate at period end (percent)	8.29%
WML Term Debt Due 2018 \| Term Notes
Debt Instrument [Line Items]
Interest rate at period end (percent)	9.65%
Non-cash interest expense	$ 2,300,000
Debt outstanding	289,700,000
Accrued paid-in-kind interest	18,400,000
Seasonal Increase to Borrowing Capacity \| Revolving line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	60,000,000
USD Denominated Sub-facility [Member] \| Revolving line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	30,000,000
USD Denominated Sub-facility with Seasonal Increase [Member] \| Revolving line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	35,000,000
CAD-Denominated Sub-facility [Member] \| Revolving line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	20,000,000
CAD Denominated Sub-facility with Seasonal Increase [Member] \| Revolving line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	25,000,000
WMLP and subsidiaries \| Revolving line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity	15,000,000
Remaining borrowing capacity	14,700,000
WMLP and subsidiaries \| Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 10,000,000.0
London Interbank Offered Rate (LIBOR) [Member] \| WML Term Debt Due 2018 \| Term Notes
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	8.50%
Debt instrument, floor interest rate (percent)	1.15%
One-month LIBOR [Member] \| Term Loan Facility Due 2020 [Member] \| Term Notes
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	6.50%
Percentage added to the base rate before including the basis spread (percent)	1.00%
Two-month LIBOR [Member] \| Term Loan Facility Due 2020 [Member] \| Term Notes
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	6.50%
Three-month LIBOR [Member] \| Term Loan Facility Due 2020 [Member] \| Term Notes
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	6.50%
Six-month LIBOR [Member] \| Term Loan Facility Due 2020 [Member] \| Term Notes
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	6.50%
Federal Funds Rate [Member] \| Term Loan Facility Due 2020 [Member] \| Term Notes
Debt Instrument [Line Items]
Percentage added to the base rate before including the basis spread (percent)	0.05%
Federal Funds Rate plus 0.05% [Member] \| Term Loan Facility Due 2020 [Member] \| Term Notes
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	5.50%
One-month LIBOR plus 1% [Member] \| Term Loan Facility Due 2020 [Member] \| Term Notes
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	5.50%
Minimum \| WML Term Debt Due 2018 \| Term Notes
Debt Instrument [Line Items]
Paid-in-kind interest (percent)	1.00%
Maximum \| WML Term Debt Due 2018 \| Term Notes
Debt Instrument [Line Items]
Paid-in-kind interest (percent)	3.00%