Property, Plant and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Accumulated amortization for assets capitalized under capital leases	$ 28,000	$ 714,000
Interest cost capitalized in PP&E	14,100,000	4,000,000	400,000
PP&E [Member]
Property, Plant and Equipment [Line Items]
Interest cost capitalized in PP&E	$ 13,586,000	$ 3,861,000
Minimum [Member] | Chemical Processing Plants and Plant Infrastructure [Member]
Property, Plant and Equipment [Line Items]
Useful lives in years	15 years
Minimum [Member] | Production, fabrication, and assembly equipment [Member]
Property, Plant and Equipment [Line Items]
Useful lives in years	7 years
Minimum [Member] | Processing Plant Components [Member]
Property, Plant and Equipment [Line Items]
Useful lives in years	3 years
Minimum [Member] | Trucks, Automobiles, Trailers, and Other Rolling Stock [Member]
Property, Plant and Equipment [Line Items]
Useful lives in years	3 years
Maximum [Member] | Chemical Processing Plants and Plant Infrastructure [Member]
Property, Plant and Equipment [Line Items]
Useful lives in years	30 years
Maximum [Member] | Production, fabrication, and assembly equipment [Member]
Property, Plant and Equipment [Line Items]
Useful lives in years	15 years
Maximum [Member] | Processing Plant Components [Member]
Property, Plant and Equipment [Line Items]
Useful lives in years	10 years
Maximum [Member] | Trucks, Automobiles, Trailers, and Other Rolling Stock [Member]
Property, Plant and Equipment [Line Items]
Useful lives in years	7 years