LOSS PER SHARE (Details)	12 Months Ended
Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2019 CNY (¥) ¥ / shares shares	Dec. 31, 2018 CNY (¥) ¥ / shares shares	Dec. 31, 2017 CNY (¥) ¥ / shares shares
Numerator:
Net loss attributable to ordinary shareholders before accretion on redeemable noncontrolling interest	$ (25,538,677)	¥ (177,795,168)	¥ (217,092,926)	¥ (118,165,850)
Accretion on redeemable noncontrolling interest	1,842,569	12,827,598	40,918,773	57,126,233
Net loss attributable to ordinary shareholders	$ (27,381,246)	¥ (190,622,766)	¥ (258,011,699)	¥ (175,292,083)
Denominator:
Denominator for basic and diluted loss per share - weighted-average shares outstanding	106,407,008	106,407,008	62,114,760	33,426,448
Loss per share - Basic and diluted \| (per share)	$ (0.26)	¥ (1.79)	¥ (4.15)	¥ (5.24)

Earnings Per Share Basic And Diluted Numerator [Abstract]

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Weighted Average Number Basic And Diluted, Shares Outstanding [Abstract]

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount, before tax, of income (loss) attributable to parent. Includes, but is not limited to, income (loss) from continuing operations, discontinued operations and equity method investments.

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Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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