SUMMARY OF PRINCIPAL ACCOUNTING POLICIES (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
SUMMARY OF PRINCIPAL ACCOUNTING POLICIES
Cash and cash equivalents	$ 549,543,359	$ 228,249,512	$ 141,968,182	$ 343,994,679
Restricted cash	439,961,661	451,153,156
Bank borrowings due within one year	725,512,738us-gaap_DebtCurrent	778,512,504us-gaap_DebtCurrent
Operating cash flow	265,105,593	229,548,624	(147,758,937)
Allowance for doubtful receivables
Receivable from Sinosure recorded in prepaid expenses and other current assets	$ 643,457	$ 451,898	$ 9,515,899

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

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