Organization and principal activities (Details 1) - CNY (¥) ¥ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Statement [Line Items]
Total current assets	¥ 663,089	¥ 615,611
Total non-current assets	45,159	48,137
Total assets	708,248	663,748
Total current liabilities	261,944	237,586
VIEs [Member]
Statement [Line Items]
Total current assets	663,089	615,611
Total non-current assets	45,159	48,137
Total assets	708,248	663,748
Total current liabilities	261,944	237,587
Total liabilities	¥ 261,944	¥ 237,587

Expiry date 2020-01-01: The amount of resources: (a) controlled by the entity as a result of past events; and (b) from which future economic benefits are expected to flow to the entity. Effective 2020-01-01: The amount of a present economic resource controlled by the entity as a result of past events. Economic resource is a right that has the potential to produce economic benefits.

Expiry date 2020-01-01: The amount of present obligations of the entity arising from past events, the settlement of which is expected to result in an outflow from the entity of resources embodying economic benefits. Effective 2020-01-01: The amount of a present obligation of the entity to transfer an economic resource as a result of past events. Economic resource is a right that has the potential to produce economic benefits.

+ References + Details