Consolidated Statements of Changes in Shareholders' Equity ¥ in Thousands, $ in Thousands |
CNY (¥) |
USD ($) |
Ordinary shares
CNY (¥)
shares
|
Ordinary shares
USD ($)
shares
|
Additional paid-in capital
CNY (¥)
|
Additional paid-in capital
USD ($)
|
Accumulated other comprehensive income
CNY (¥)
|
Accumulated other comprehensive income
USD ($)
|
Retained Earnings
CNY (¥)
|
Retained Earnings
USD ($)
|
Noncontrolling interests
CNY (¥)
|
Noncontrolling interests
USD ($)
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Beginning balance, Amount at Dec. 31, 2014 | ¥ 3,665,423 | ¥ 7,484 | ¥ 2,649,111 | ¥ 5,932 | ¥ 1,002,896 | |||||||
| Beginning balance, Shares at Dec. 31, 2014 | shares | 110,602,163 | 110,602,163 | ||||||||||
| Net income / (loss) | 990,649 | 990,649 | ||||||||||
| Other comprehensive income: | ||||||||||||
| Foreign currency translation adjustments | 56,821 | 56,821 | ||||||||||
| Exercise and vesting of share-based awards | 30,198 | ¥ 151 | 30,047 | |||||||||
| Exercise and vesting of share-based awards, Shares | shares | 2,452,407 | 2,452,407 | ||||||||||
| Share-based compensation | 107,945 | 107,945 | ||||||||||
| Ending balance, Amount at Dec. 31, 2015 | 4,851,036 | ¥ 7,635 | 2,787,103 | 62,753 | 1,993,545 | |||||||
| Ending balance, Shares at Dec. 31, 2015 | shares | 113,054,570 | 113,054,570 | ||||||||||
| Net income / (loss) | 1,216,223 | 1,227,914 | ¥ (11,691) | |||||||||
| Other comprehensive income: | ||||||||||||
| Foreign currency translation adjustments | 62,256 | 62,256 | ||||||||||
| Capital injection from noncontrolling interests shareholder | 2,500 | 2,500 | ||||||||||
| Exercise and vesting of share-based awards | 23,805 | ¥ 149 | 23,656 | |||||||||
| Exercise and vesting of share-based awards, Shares | shares | 2,242,654 | 2,242,654 | ||||||||||
| Share-based compensation | 195,393 | 195,393 | ||||||||||
| Ending balance, Amount at Dec. 31, 2016 | 6,351,213 | ¥ 7,784 | 3,006,152 | 125,009 | 3,221,459 | (9,191) | ||||||
| Ending balance, Shares at Dec. 31, 2016 | shares | 115,297,224 | 115,297,224 | ||||||||||
| Net income / (loss) | 1,994,459 | $ 306,542 | 2,001,619 | (7,160) | ||||||||
| Other comprehensive income: | ||||||||||||
| Foreign currency translation adjustments | (55,055) | (8,462) | (55,055) | |||||||||
| Dividends declared (RMB5.08 (US$0.76) per Class A ordinary share; RMB595,779 (US$91,570) to Class A ordinary shareholders) | (595,779) | (595,779) | ||||||||||
| Exercise and vesting of share-based awards | 62,662 | ¥ 125 | 62,537 | |||||||||
| Exercise and vesting of share-based awards, Shares | shares | 1,843,632 | 1,843,632 | ||||||||||
| Share-based compensation | 177,786 | 177,786 | ||||||||||
| Ending balance, Amount at Dec. 31, 2017 | ¥ 7,935,286 | $ 1,219,632 | ¥ 7,909 | $ 1,216 | ¥ 3,246,475 | $ 498,974 | ¥ 69,954 | $ 10,752 | ¥ 4,627,299 | $ 711,203 | ¥ (16,351) | $ (2,513) |
| Ending balance, Shares at Dec. 31, 2017 | shares | 117,140,856 | 117,140,856 |