REDEEMABLE NON-CONTROLLING INTERESTS (Details) - CNY (¥) ¥ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
REDEEMABLE NON-CONTROLLING INTERESTS
Balance at beginning of year	¥ 225,645	¥ 228,230
Stock-based compensation		7,911
Net loss attributable to mezzanine equity holders	(8,671)	(10,496)
Balance at end of year	¥ 216,974	¥ 225,645
Lagou Information Limited
REDEEMABLE NON-CONTROLLING INTERESTS
Percentage of equity interest acquired			66.00%

Amount of stock-based compensation relating to redeemable non-controlling interest.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Publisher FASB
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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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- Definition

As of the reporting date, the carrying amount of 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. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of preferred shares (regardless of class), preferred partnership units (regardless of class), preferential membership interests, or any other form of preferred equity regardless of investee entity legal form.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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