Commitments and Contingencies (Additional Information) (Detail) $ in Thousands		1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 21, 2014 USD ($)	Oct. 31, 2016 USD ($)	Mar. 31, 2017 USD ($) settlement	Dec. 31, 2015 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2016 USD ($)
Environmental Loss Contingencies [Line Items]
Environmental Loss contingency accrual			$ 48,217			$ 48,817
Pending Litigation [Member]
Environmental Loss Contingencies [Line Items]
Maximum Expected Damages		$ 167
LDEQ [Member] | Settled Litigation [Member]
Environmental Loss Contingencies [Line Items]
Number of claims settled | settlement			2
Amount of settlement for compliance violations			$ 192
LDEQ [Member] | Pending Litigation [Member]
Environmental Loss Contingencies [Line Items]
Maximum Expected Damages			100
Natrium [Member] | Axiall Corporation [Member] | Settled Litigation [Member]
Environmental Loss Contingencies [Line Items]
Payments for environmental loss contingencies					$ 449
Lake Charles, Louisiana [Member] | Axiall Corporation [Member] | Environmental Protection Agency [Member] | Settled Litigation [Member]
Environmental Loss Contingencies [Line Items]
Amount of settlement for compliance violations				$ 878
Culvert City, Kentucky and Lakes Charles, Louisiana [Member] | Environmental Protection Agency [Member] | Pending Litigation [Member]
Environmental Loss Contingencies [Line Items]
Maximum Expected Damages	$ 100
Maximum [Member]
Environmental Loss Contingencies [Line Items]
Environmental Exit Costs, Reasonably Possible Additional Loss			80
Minimum [Member]
Environmental Loss Contingencies [Line Items]
Environmental Exit Costs, Reasonably Possible Additional Loss			$ 40