Non-controlling interests - Balance of redeemable non-controlling interests (Details) ¥ in Thousands	12 Months Ended
Dec. 31, 2022 CNY (¥)
Redeemable Non-Controlling Interest [Roll Forward]
Balance at beginning	¥ 30,500
Add: Capital contribution	10,000
Less: Comprehensive loss	(464)
Add: Accretion of redeemable non-controlling interests	714
Less: Deconsolidation of Suzhou Photon-Matrix	(40,750)
Balance at ending	¥ 0

Redeemable Non-Controlling Interest

No definition available.

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- Definition

The amount of the reduction or elimination during the period of a redeemable noncontrolling interest resulting from the parent's loss of control and deconsolidation of the entity in which one or more outside parties had a noncontrolling interest.

+ References

No definition available.

+ Details

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- Definition

Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

+ References

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-Topic 810
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- Definition

Amount after tax of other comprehensive income (loss) attributable to noncontrolling interests.

+ References

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-Topic 810
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-Topic 220
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- Definition

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

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- Definition

Value of accretion of temporary equity during the period due to unpaid interest.

+ References

No definition available.

+ Details

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