ACCOUNTS RECEIVABLE (Tables)

12 Months Ended

Dec. 31, 2012

ACCOUNTS RECEIVABLE [Abstract]

Schedule of Accounts Receivable

	December 31,
	2011			2012
Accounts receivable		84,634,677			129,476,266
Allowance for doubtful accounts		(1,323,490	)		(1,503,621	)
Accounts receivable, net		83,311,187			127,972,645

Schedule of Allowance for Doubtful Accounts

	December 31,
	2010			2011			2012
Balance at the beginning of year		348,862			304,796			1,323,490
Additions/(reversals) charged to bad debt expense		(209,845	)		1,576,739			1,137,574
Reversals/(write-offs) charged against the allowance		165,779			(558,045	)		(957,443	)
Balance at the end of year		304,796			1,323,490			1,503,621