COMMITMENTS AND CONTINGENCIES - Summary of Environmental Liability Associated with Potsdam (Detail) - Potsdam Environmental Remediation Liability - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning balance	$ 5,221	$ 5,142
Obligations settled	(255)	0
Ending balance	4,966	5,201
Accretion Expense
Accrual for Environmental Loss Contingencies [Roll Forward]
Accretion expense	$ 0	$ 59

Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 25
-Paragraph 2
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Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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Amount of cash outflow to settle environmental loss contingencies.

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