Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Summary Of Significant Accounting Policies [Line Items]
Adjustments for cost report settlements	$ 299,710
Minimum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	9 years
Prepaid and Other Current Assets
Summary Of Significant Accounting Policies [Line Items]
Cost settlements adjustment amount	917,665	617,955
Restricted cash	$ 600,000	$ 700,000