v3.20.1

Share-based Compensation - Additional Information (Details) |  |  |  | 1 Months Ended | 9 Months Ended | 12 Months Ended |  |  |
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Oct. 26, 2018 shares | Dec. 30, 2016 shares | Jan. 07, 2008 shares | Mar. 31, 2019 $ / shares shares | Jan. 31, 2019 $ / shares shares | Dec. 31, 2018 shares | Nov. 30, 2018 $ / shares shares | Jul. 31, 2018 shares | Aug. 31, 2017 $ / shares shares | Jan. 31, 2017 $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2019 USD ($) $ / shares shares | Dec. 31, 2018 CNY (¥) shares | Dec. 31, 2018 USD ($) $ / shares shares | Dec. 31, 2019 CNY (¥) shares | Oct. 31, 2007 shares | Apr. 30, 2005 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation costs accelerated and recognized | ¥ |  |  |  |  |  |  |  |  |  |  |  |  | ¥ 877,321 |  |  |  |
ATA Online |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation costs accelerated and recognized | ¥ |  |  |  |  |  |  |  |  |  |  |  |  | ¥ 6,753,771 |  |  |  |
Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  |  |  |  |  | 50,000 | 70,000 | 1,053,150 | 1,053,150 |  |  |
Granted (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  | $ 2.35 | $ 0.50 |  | $ 0.58 |  |  |
Options cancelled (in shares) |  |  |  |  |  |  | 1,772,584 |  |  |  |  |  | 1,901,752 | 1,901,752 |  |  |
Vested cancelled (in shares) |  |  |  |  |  |  | 1,215,114 |  |  |  |  |  |  |  |  |  |
Total unrecognized compensation expense | ¥ |  |  |  |  |  |  |  |  |  |  |  |  |  |  | ¥ 331,885 |  |
Weighted average period over which unrecognized compensation expense is expected to be recognized |  |  |  |  |  |  |  |  |  |  |  | 2 years 9 months 10 days |  |  |  |  |
Options | ATA Online |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options cancelled (in shares) |  |  |  |  |  |  |  | 129,168 |  |  |  |  |  |  |  |  |
Options | Employees and officers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  | 75.00% | 75.00% |  | 75.00% |  |  | 75.00% |  |  |  |  |  |  |
Vesting period for remaining 75% shares |  |  |  | 36 months | 36 months |  | 36 months |  |  | 36 months |  |  |  |  |  |  |
Vesting rate on the first anniversary (as a percent) |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |
Granted (in shares) |  |  |  | 20,000 | 50,000 | 1,772,584 | 690,000 |  |  | 900,000 |  |  |  |  |  |  |
Granted (in dollars per share) | $ / shares |  |  |  | $ 0.532 | $ 0.4868 |  | $ 0.578 |  |  | $ 1.705 |  |  |  |  |  |  |
Vesting rate at the end of each year from the grant date over 4 years (as a percent) |  |  |  | 25.00% | 25.00% |  | 25.00% |  |  |  |  |  |  |  |  |  |
Vested immediately on the grant date (in shares) |  |  |  |  |  | 1,412,336 |  |  |  |  |  |  |  |  |  |  |
Options | Employee |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  |  |  |  |  |  | 75.00% |  |  |  |  |  |  |  |
Vesting period for remaining 75% shares |  |  |  |  |  |  |  |  | 36 months |  |  |  |  |  |  |  |
Vesting rate on the first anniversary (as a percent) |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  | 363,150 |  | 50,000 |  |  |  |  |  |  |  |
Granted (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  | $ 2.35 |  |  |  |  |  |  |  |
Options | Certain employee and officer |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  | 4 years |  |  |  |  |  |  |  |  |  |
Share options issued (in shares) |  |  |  |  |  |  | 1,452,600 |  |  |  |  |  |  |  |  |  |
Non-vested shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-vested shares granted |  |  |  |  |  |  |  |  |  |  |  |  | 2,572,584 | 2,572,584 |  |  |
Nonvested cancelled (in shares) |  |  |  |  |  |  | 557,470 |  |  |  |  |  | 1,262,250 | 1,262,250 |  |  |
Total unrecognized compensation expense | ¥ |  |  |  |  |  |  |  |  |  |  |  |  |  |  | ¥ 2,077,009 |  |
Weighted average period over which unrecognized compensation expense is expected to be recognized |  |  |  |  |  |  |  |  |  |  |  | 2 years 2 months 1 day |  |  |  |  |
Additional disclosures |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total fair value of shares vested | $ |  |  |  |  |  |  |  |  |  |  | $ 148,500 | $ 461,309 |  | $ 2,591,875 |  |  |
Number of vested shares withheld upon vesting to satisfy the minimum tax withholding obligation |  |  |  |  |  |  |  |  |  |  | 11,252 | 28,456 | 93,496 | 93,496 |  |  |
Non-vested shares | ATA Online |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nonvested cancelled (in shares) |  |  |  |  |  |  |  | 1,262,250 |  |  |  |  |  |  |  |  |
Non-vested shares | Employees and officers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |  |  |
Non-vested shares granted |  |  |  |  |  |  |  |  |  | 2,700,000 |  |  |  |  |  |  |
Non-vested shares | Directors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  |  |  |  | 75.00% |  |  |  |  |  |  |  |  |  |
Vesting period for remaining 75% shares |  |  |  |  |  |  | 36 months |  |  |  |  |  |  |  |  |  |
Non-vested shares granted |  |  |  |  |  |  | 800,000 |  |  |  |  |  |  |  |  |  |
Vesting rate on the first anniversary (as a percent) |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |
Grant date over 4 years | Non-vested shares | Employees and officers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |
2005 Share incentive plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,310,300 | 2,894,000
2005 Share incentive plan | Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expiration term |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |
2005 Share incentive plan | Vesting on first anniversary | Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |
2005 Share incentive plan | Vesting ratably over following 36 months | Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 75.00% |  |  |  |  |
2008 Share incentive plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares authorized |  | 5,726,763 | 336,307 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual increase in shares reserved (as a percent) |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual increase in shares reserved (in shares) |  |  | 336,307 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expiration term |  | 10 years | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |
2008 Share incentive plan | Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expiration term |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |
2008 Share incentive plan | Non-vested shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period for remaining 75% shares |  |  |  |  |  |  |  |  |  |  |  | 36 months |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |
2008 Share incentive plan | Vesting on first anniversary | Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |
2008 Share incentive plan | Vesting ratably over following 36 months | Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 75.00% |  |  |  |  |
2008 Share incentive plan | Grant date over 4 years | Non-vested shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |
Amendment and Restatement of 2008 Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual increase in shares reserved (as a percent) | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common shares reserved for issuance | 6,965,846 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Second Amendment and Restatement of 2008 Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common shares reserved for issuance |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,423,815 |  |

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- Definition Represents the percentage of shares vesting over the following 36 months from the first anniversary date of the award. + References No definition available. + Details
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- Definition Represents the percentage of shares vesting at the first anniversary date of the award. + References No definition available. + Details
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- Definition Represents the maximum percentage of the number of shares of common stock by which the number of shares authorized shall be increased under the plan. + References No definition available. + Details
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- Definition Number of options or other stock instruments for which the right to exercise has cancelled under the terms of the plan agreements. + References No definition available. + Details
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- Definition Number of non-vested options cancelled. + References No definition available. + Details
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- Definition Number of vested options cancelled. + References No definition available. + Details
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- Definition Represents the period of time from the first anniversary date when 75 percent of shares are vested. + References No definition available. + Details
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- Definition Aggregate number of common shares reserved for future issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost. + References No definition available. + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition 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. + References No definition available. + Details
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- Definition Number of additional shares authorized for issuance under share-based payment arrangement. + References No definition available. + Details
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- Definition Number of shares authorized for issuance under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition Number of shares issued under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. + References No definition available. + Details
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- Definition Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement. + References No definition available. + Details
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- Definition Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement. + References No definition available. + Details
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