Fair Value of Financial Instruments - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Maturity of cash flow hedges in months	12 months
Reclassification to finished goods inventory	$ 0	$ 0	$ 0
Recourse debt [Member] | 5.30% Senior Notes due in 2025 ("2025 Notes") [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest Rate	5.30%
Maturity Dates	Aug. 31, 2025
Interest Rate Swaps [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative notional amount	$ 496,544,000	789,600,000
Gross asset at fair value	5,304,000	10,600,000
Gross liability at fair value	5,245,000	12,100,000
Recognized gross gain on derivative	7,192,000	7,000,000
Cash Flow Hedging [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Hedge contracts outstanding	0	0
Reclassified net gain from accumulated other comprehensive income (loss) to consolidated statement of operations	$ 5,600,000	$ 44,900,000	$ 0