FAIR VALUE MEASUREMENTS (Changes in fair value of rate swap derivative) (Details)	12 Months Ended
Dec. 31, 2020 CNY (¥)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2018 CNY (¥)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Change in fair value of interest rate swap	¥ 78,878,089	$ 12,088,596	¥ 69,974,512	¥ (9,701,051)
Interest Rate Swap [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at January 1,	61,271,965		12,786,001	26,486,388
Change in fair value of interest rate swap	78,878,089		69,974,512	(9,701,051)
Cash settlement	¥ (140,150,054)		(21,488,548)	(3,999,336)
Balance at December 31,			¥ 61,271,965	¥ 12,786,001

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.

No definition available.

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Amount of settlements of financial instrument classified as a derivative asset (liability) after deduction of derivative liability, measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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