ORDINARY SHARES AND STATUTORY RESERVE (Statutory reserves and restricted net assets and Dividend) (Details) - CNY (¥) ¥ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
ORDINARY SHARES AND STATUTORY RESERVE
Statutory Reserves, Percentage of Appropriation From Net Profit	10.00%
Statutory Reserves, Balance As Percentage to Capital	50.00%
Statutory Reserves for Private Schools Requiring Reasonable Returns, Percentage of Appropriation From Net Profit	25.00%
Statutory Reserves for Private Schools Not Requiring Reasonable Returns, Percentage of Expected Annual Increase in Net Assets	25.00%
Appropriations	¥ 6,780	¥ 19,037	¥ 16,736
Statutory reserve	201,381	194,601
Restricted net assets	1,228,153	1,558,879
Cash dividends	¥ 0	¥ 0	¥ 0

Ordinary Shares and Statutory Reserve [Abstract]

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- Definition

The amount of statutory capital and surplus appropriated during the period.

+ References

No definition available.

+ Details

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- Definition

Under PRC rules and regulations, Tarena International's PRC subsidiaries, consolidated VIEs, and the subsidiaries of the VIEs (the "PRC Entities") are required to appropriate 10% of their net profit, as determined in accordance with PRC accounting rules and regulations, to a statutory surplus reserve until the reserve balance reaches 50% of their registered capital.

+ References

No definition available.

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- Definition

Represents the appropriation percentage of increase in net assets for private schools not requiring reasonable returns.

+ References

No definition available.

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- Definition

Represents the appropriation percentage from net profit for private schools that looking for reasonable returns.

+ References

No definition available.

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- Definition

Represents the appropriation percentage from net profit, that has to be contributed till attain the statutory reserve fixed by PRC.

+ References

No definition available.

+ Details

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- Definition

Amount of restricted net assets of consolidated and unconsolidated subsidiaries as of the end of the most recently completed fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(3)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
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-Name Accounting Standards Codification
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-SubTopic 505
-Section 50
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479989/944-505-50-1

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