Debt Schedule of Debt (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Debt Instrument [Line Items]
Amortization of Intangible Assets	$ 1,000	$ 900	$ 1,600	$ 1,800
Total debt, net of unamortized debt discount	171,407		171,407		$ 136,610
Less current maturities	(43,373)		(43,373)		(29,100)
Long-term debt, net of current maturities and unamortized discount	128,034		128,034		107,510
Retail Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	28,928		28,928		22,750	[1]
Texadian Uncommitted Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	0		0		26,500
Mid Pac Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	48,958		48,958		0
Tranche B Loan [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	$ 93,521		$ 93,521		$ 87,360

[1] Fair value approximates carrying value due to the floating rate interest which approximates a current market rate.