Accounts Receivable (Tables)

9 Months Ended

Sep. 30, 2012

Accounts Receivable [Abstract]

Changes in the Company's allowance for doubtful accounts

	For the three months ended				For the nine months ended
	September 30,				September 30,
	2011		2012		2011			2012
	(Unaudited)		(Unaudited)		(Unaudited)			(Unaudited)
Beginning balance	$	15,238	$	22,352	$	76,436		$	22,292
Bad debt expense (recoveries)		821		837		(60,377	)		6,805
Uncollectible accounts written off		—		—		—			(5,908	)
Ending balance	$	16,059	$	23,189	$	16,059		$	23,189