Prepayments And Other Current Assets - Summary of Prepayments and Other Current Assets (Detail)	Dec. 31, 2021 CNY (¥)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 CNY (¥)
Prepaid Expense and Other Assets [Abstract]
Prepayments for vehicles	¥ 712,544,814	$ 111,813,830	¥ 403,116,119
Vehicles and telematics devices	131,722,840	20,670,188	54,725,824
Deposits held by third-parties	48,176,225	7,559,901	18,171,682
Other receivables from third parties	33,092,696	5,192,966	10,461,282
Accrued input value-added tax	22,922,301	3,597,009	26,623,275
Prepaid expenses	9,977,021	1,565,612	14,331,513
Interest receivables	5,655,031	887,398	4,889,508
Loan to suppliers	0	0	1,573,800
Others	18,857,709	2,959,187	24,467,956
Total	¥ 982,948,637	$ 154,246,091	¥ 558,360,959

Amount of trust deposits.

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Amount of loan to certain collaborative suppliers according to arrangements.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount of current assets classified as other.

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Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of value added taxes due either from customers arising from sales on credit terms, or as previously overpaid to tax authorities. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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