Accounts Receivable, Net

12 Months Ended

Dec. 31, 2018

Receivables [Abstract]

ACCOUNTS RECEIVABLE, NET

6. ACCOUNTS RECEIVABLE, NET

		As of December 31,
		2017		2018			2018
		RMB		RMB			US$
Accounts receivable	2,260,070				2,984,090			434,018
Allowance for doubtful accounts	(24,686		)		(94,856	)		(13,796	)
Accounts receivable, net	2,235,384				2,889,234			420,222

The following table presents movement of the allowance for doubtful accounts:

	As of December 31,
	2016		2017			2018			2018
	RMB		RMB			RMB			US$
Balance at the beginning of the year	21,913			19,719			24,686			3,590
Provisions	7,245			56,048			85,745			12,471
Write-offs	(9,439	)		(51,081	)		(15,575	)		(2,265	)
Balance at the end of the year	19,719			24,686			94,856			13,796