Cash and cash equivalents (Tables)

12 Months Ended

Dec. 31, 2017

Cash and cash equivalents [Abstract]

Schedule of cash and cash equivalents balance

	December 31, 2016				December 31, 2017
	Amount		RMB equivalent		Amount		RMB equivalent
RMB		1,536,947		1,536,947		1,627,044		1,627,044
US$		6,171		42,796		151,529		990,388
Total				1,579,743				2,617,432