v3.20.1

Subsequent Events - Additional information (Details) - ATA Online Sale Transaction $ in Millions | 1 Months Ended |
--- | --- | ---
Mar. 31, 2020 CNY (¥) | Mar. 31, 2020 USD ($) | Dec. 31, 2019 CNY (¥)
Subsequent Event [Line Items] |  |  |
Loss contingency accrued |  |  | ¥ 0
Subsequent Events |  |  |
Subsequent Event [Line Items] |  |  |
Total consideration | $ |  | $ 200.0 |
Subsequent Events | Alpha Advantage Global Limited and Dynamic Fame Limited |  |  |
Subsequent Event [Line Items] |  |  |
Attorney’s fees and other litigation costs | ¥ 15,000,000 |  |
Subsequent Events | Mr. Kevin Xiaofeng Ma | Alpha Advantage Global Limited |  |  |
Subsequent Event [Line Items] |  |  |
Loss contingency, damages sought, value | 95,000,000 |  |
Attorney’s fees and other litigation costs | 1,500,000 |  |
Subsequent Events | Mr. Kevin Xiaofeng Ma | Dynamic Fame Limited |  |  |
Subsequent Event [Line Items] |  |  |
Loss contingency, damages sought, value | 5,000,000 |  |
Attorney’s fees and other litigation costs | ¥ 500,000 |  |

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- Definition Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585 + Details
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