| Dec 31, 2013 | Dec 31, 2014 | Dec 31, 2015 | Dec 31, 2016 | Dec 31, 2017 | Dec 31, 2018 | Dec 31, 2019 | Dec 31, 2022 | Dec 31, 2023 |
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| Cash and cash equivalents | 581 | 355 | 818 | 337 | 228 | 195 | 105 | 106 | 86 |
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| Restricted cash, current | - | - | - | - | - | - | 219 | 1 | 4 |
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| Short-term investments | 10 | 455 | 63 | 43 | 56 | 16 | 195 | 109 | 107 |
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| Accounts receivable, net | 45 | 50 | 148 | 94 | 67 | 61 | 66 | 31 | 22 |
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| Prepayments and other current assets | 32 | 30 | 60 | 40 | 33 | 28 | 32 | 109 | 68 |
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| Loans receivable, net | - | 80 | 267 | 42 | 129 | 118 | 60 | 47 | 32 |
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| Amounts due from related parties | - | - | - | - | - | - | - | 4 | 1 |
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| Total current assets | 964 | 1,180 | 1,515 | 793 | 748 | 669 | 687 | 407 | 320 |
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| Property and equipment, net | 221 | 217 | 327 | 320 | 622 | 728 | 695 | 635 | 469 |
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| Deferred tax assets | - | - | - | - | - | - | 7 | 5 | 17 |
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| Restricted Cash, Noncurrent | - | - | - | - | 40 | 7 | 42 | 3 | - |
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| Long-term investments | - | 121 | 245 | 232 | 471 | 373 | 342 | 98 | 105 |
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| Long-term time deposits | 38 | 87 | 138 | 241 | 59 | 1 | 1 | - | 1 |
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| Right-of-use assets | - | - | - | - | - | - | - | 31 | 16 |
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| Other non-current assets | 23 | 17 | 11 | 7 | 2 | 5 | 39 | 29 | 18 |
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| Total non-current assets | 541 | 564 | 781 | 822 | 1,252 | 1,156 | 1,126 | 801 | 627 |
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| Total assets | 1,505 | 1,744 | 2,295 | 1,615 | 2,000 | 1,824 | 1,813 | 1,209 | 947 |
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| Short-Term Debt and Loans Payable, Current | - | - | - | - | - | - | - | 43 | 18 |
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| Bond payable | - | - | - | - | - | - | - | 103 | 51 |
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| Deferred revenue | 115 | 119 | 145 | 130 | 169 | 163 | 134 | 50 | 56 |
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| Accrued expenses and other liabilities | - | - | - | - | - | - | - | 67 | 54 |
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| Income tax payable | 44 | 35 | 10 | 6 | 4 | 4 | 4 | 1 | 1 |
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| Other Liabilities, Current | - | - | - | - | - | - | - | 91 | 35 |
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| Total current liabilities | 446 | 500 | 1,076 | 696 | 582 | 601 | 640 | 354 | 215 |
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| Loans Payable, Noncurrent | 181 | 100 | - | 65 | 114 | 123 | 184 | 60 | 168 |
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| Deferred tax liabilities | - | - | - | - | - | - | 91 | 63 | 63 |
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| Other non-current liabilities | 0 | 0 | 0 | 0 | 146 | 153 | 138 | 140 | 118 |
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| Total non-current liabilities | 616 | 611 | 365 | 431 | 678 | 628 | 582 | 263 | 348 |
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| Total liabilities | 1,062 | 1,112 | 1,441 | 1,127 | 1,260 | 1,229 | 1,222 | 617 | 563 |
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| Commitments and contingencies | - | - | - | - | - | - | - | - | - |
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| Common Class A | 7 | 7 | 9 | 9 | 9 | 9 | 9 | 9 | 9 |
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| Common Class B | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
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| Additional paid-in capital | 89 | 101 | 478 | 489 | 501 | 518 | 529 | 545 | 545 |
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| Accumulated other comprehensive loss | 43 | 50 | -10 | -81 | 138 | -76 | -98 | -9 | -37 |
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| Retained earnings (accumulated deficit) | 301 | 471 | 374 | 204 | 226 | 277 | 270 | 155 | -25 |
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| Less: Treasury shares (5,755,007 shares as of December 31, 2022 and 2023, respectively.) | - | - | - | - | - | - | - | 111 | 111 |
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| Total shareholders' equity | 443 | 633 | 855 | 488 | 740 | 595 | 590 | 592 | 384 |
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| Total liabilities and shareholders' equity | 1,505 | 1,744 | 2,295 | 1,615 | 2,000 | 1,824 | 1,813 | 1,209 | 947 |
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