Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Represents the functional currency equivalent of cash and cash equivalents denominated in foreign currency.

+ References

No definition available.

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- Definition

Represents the functional currency equivalent of restricted cash denominated in foreign currency.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- References

No definition available.

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SUMMARY OF PRINCIPAL ACCOUNTING POLICIES (Foreign Currency and Derivative Financial Instruments) (Narrative) (Details)	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2016 CNY (¥)	Dec. 31, 2015 CNY (¥)
Foreign currency [Line Items]
Cash and cash equivalents, functional currency equivalent of foreign currency denominated amount	$ 16,157,889	$ 5,342,001		¥ 112,184,192	¥ 34,604,501
Restricted cash	95,865,515	140,337,531		¥ 613,666,780	¥ 560,065,172
Restricted cash, functional currency equivalent of foreign currency denominated amount	88,386,426	86,458,941
Derivative financial instruments
Net (gains) losses on derivative instruments from foreign currency forward exchange contracts	(4,591,991)	$ 6,030,915	$ (6,057,941)
Foreign exchange contracts [Member] \| Non-designated [Member]
Foreign currency [Line Items]
Notional amount of outstanding foreign currency forward exchange contracts	$ 50,605,200