Line of Credit and Term Loan - Additional Information (Detail) (USD $)	3 Months Ended	6 Months Ended		6 Months Ended			6 Months Ended			6 Months Ended
	Jun. 30, 2014 Term Loan Facility	Jun. 30, 2014 Credit Agreement	Jun. 30, 2014 Credit Agreement Term Loan Facility	Jun. 30, 2014 Credit Agreement Term Loan Facility Eurodollar Rate Loans	Jun. 30, 2014 Credit Agreement Term Loan Facility Base Rate Loan	Jun. 30, 2014 Credit Agreement Revolving Loans	Jun. 30, 2014 Credit Agreement Revolving Loans Eurodollar Rate Loans	Jun. 30, 2014 Credit Agreement Revolving Loans Base Rate Loan	Jun. 30, 2014 Credit Agreement Revolving Credit Facilities	Jun. 30, 2014 Bank of America Credit Agreement	Jun. 30, 2014 Bank of America Credit Agreement Term Loan Facility	Jun. 30, 2014 Bank of America Credit Agreement Revolving Credit Facilities
Line of Credit Facility [Line Items]
Line of credit, total borrowings			$ 52,220,000						$ 90,140,000	$ 150,000,000
Line of credit, maturity period											3 years	3 years
Line of credit, value											60,000,000	90,000,000
Maturity date of debt instrument											May 23, 2016	May 23, 2016
Line of credit, pledge equity interest										65.00%
Line of credit, interest rate description		The interest rates applicable to the loans incurred under the Credit Agreement are (a) with respect to Revolving Loans, (i) the Eurodollar Rate plus 1.25% with respect to Eurodollar Loans and (ii) the Base Rate plus 0.25% with respect to Base Rate Loans, and (b) with respect to the Term Loan, (i) the Eurodollar Rate plus 1.50% with respect to Eurodollar Loans and (ii) the Base Rate plus 0.50% with respect to Base Rate Loans (each as defined in the Credit Agreement).
Line of credit, interest rate				1.50%	0.50%		1.25%	0.25%
Line of credit, effective interest rate			1.72735%			1.47735%
Line of credit, principal payment	$ 1,875,000