Allowances for Doubtful Accounts (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Accounting Policies [Abstract]
Balance at Beginning of Year			$ 1,659,337
Additions Recognized as Reduction to Revenues	(682,319)	(123,413)	(2,409,733)	(386,165)
Write-offs, Net of Recoveries			(1,414,984)
Balance at End of Year	$ 2,654,086		$ 2,654,086