Long-Term Debt - Additional Information (Detail) (USD $)				1 Months Ended				1 Months Ended	6 Months Ended					1 Months Ended
	Jun. 30, 2014	Dec. 15, 2011 First Amendment Rantoul Partners	Aug. 31, 2012 Second Amendment	Aug. 31, 2012 Second Amendment Minimum	Nov. 02, 2012 Third Amendment	Apr. 16, 2013 Fourth Amendement	Sep. 30, 2013 Fifth Amendment	May 22, 2014 Seventh Amendment Series A Cumulative Redeemable Perpetual Preferred Stock [Member]	Jun. 30, 2014 Line of Credit Federal Funds Rate	Jun. 30, 2014 Line of Credit Base Rate Minimum	Jun. 30, 2014 Line of Credit Base Rate Maximum	Jun. 30, 2014 Line of Credit Floating Rate Minimum	Jun. 30, 2014 Line of Credit Floating Rate Maximum	Sep. 30, 2013 Line of Credit Fifth Amendment Federal Funds Rate
Debt Instrument [Line Items]
Debt instrument interest rate, margin									0.50%	0.00%	0.75%	2.25%	3.00%	3.30%
Line of credit facility, maximum borrowing capacity		$ 50,000,000					$ 100,000,000
Line of credit facility, current borrowing capacity	38,000,000		7,000,000		12,150,000	19,500,000	38,000,000
Debt Instrument, Interest Rate, Increase				3.75%
Credit Facility	$ 19,000,000
Debt Instrument, Interest Rate, Stated Percentage	3.30%
Redeemable Perpetual Preferred Stock Reserved For Future Issuance								850,000
Preferred Stock, Dividend Rate, Percentage								10.00%