INTANGIBLE ASSETS, NET (Details) - CNY (¥) ¥ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Intangible assets
Intangible assets, gross	¥ 1,657,682	¥ 967,882
Less: accumulated amortization	(375,046)	(182,560)
Intangible assets, net	1,282,636	785,322
Amortization of intangible assets	192,486	68,688	¥ 58,312
Estimated future amortization expense
2022	235,290
2023	233,748
2024	226,890
2025	212,577
2026	206,387
Thereafter	167,744
Customer relationships
Intangible assets
Intangible assets, gross	1,641,900	952,100
Licenses
Intangible assets
Intangible assets, gross	¥ 15,782	¥ 15,782

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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