Income taxes - Valuation Allowance, Reconciliation to Statutory Rate, Effect of Tax Holiday (Details) $ / shares in Units, $ in Thousands |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
Dec. 31, 2017
USD ($)
$ / shares
|
Dec. 31, 2017
CNY (¥)
|
Dec. 31, 2016
USD ($)
$ / shares
|
Dec. 31, 2016
CNY (¥)
|
Dec. 31, 2015
USD ($)
$ / shares
|
Dec. 31, 2015
CNY (¥)
|
Dec. 31, 2014
CNY (¥)
|
Dec. 31, 2013 |
Dec. 31, 2012 |
Dec. 31, 2011 |
|
| Movement in valuation allowance | ||||||||||
| Allowance made during the year | ¥ 63,331,000 | |||||||||
| Effect of tax rate change | ¥ 6.39 | ¥ 9.54 | ||||||||
| PRC enterprise income tax (as a percent) | 25.00% | 25.00% | 25.00% | 25.00% | 25.00% | 25.00% | ||||
| Income tax expense | ¥ 98,470,000 | ¥ 123,301,000 | ¥ 157,332,000 | |||||||
| Effect of permanent differences: | ||||||||||
| Share based compensation and other permanent difference (as a percent) | 1.90% | 1.90% | 2.59% | 2.59% | 2.78% | 2.78% | ||||
| Effect of tax holiday (as a percent) | (10.72%) | (10.72%) | (8.38%) | (8.38%) | (7.54%) | (7.54%) | ||||
| Difference of tax rates of subsidiaries outside of China (as a percent) | 3.64% | 3.64% | (5.43%) | (5.43%) | (0.25%) | (0.25%) | ||||
| Effect of tax rate change (as a percent) | 6.39% | 6.39% | 9.54% | 9.54% | (3.06%) | (3.06%) | ||||
| Withholding tax for dividend distribution (as a percent) | 0.23% | 0.23% | ||||||||
| Intra-group investment disposal income subject to tax | 1.31% | 1.31% | ||||||||
| Valuation allowance (as a percent) | (1.51%) | (1.51%) | (10.23%) | (10.23%) | 3.46% | 3.46% | ||||
| Total (as a percent) | 24.70% | 24.70% | 14.63% | 14.63% | 20.39% | 20.39% | ||||
| Preferential income tax rate as an ANTE | 15.00% | 15.00% | 15.00% | 15.00% | 15.00% | 15.00% | 15.00% | 15.00% | 15.00% | |
| Aggregate amount and per share effect of the tax holiday | ||||||||||
| The aggregate amount of effect | $ | $ 42,671 | $ 70,653 | $ 58,194 | |||||||
| Per share effect-basic (in dollars per share) | $ / shares | $ 0.18 | $ 0.30 | $ 0.24 | |||||||
| Per share effect-diluted (in dollars per share) | $ / shares | $ 0.18 | $ 0.30 | $ 0.24 | |||||||
| JA Solar USA Inc. ("JA USA") | ||||||||||
| Movement in valuation allowance | ||||||||||
| Income tax expense | ¥ 0 | |||||||||
| Deferred tax assets | ||||||||||
| Movement in valuation allowance | ||||||||||
| Balance at beginning of the year | 373,793,000 | ¥ 483,649,000 | ¥ 456,925,000 | |||||||
| Allowance made during the year | 72,915,000 | 128,605,000 | 119,448,000 | |||||||
| Effect of tax rate change | (24,833,000) | |||||||||
| Reversals and utilization | (54,114,000) | (214,860,000) | (92,724,000) | |||||||
| Written off | (23,601,000) | |||||||||
| Balance at end of the year | 367,761,000 | 373,793,000 | 483,649,000 | ¥ 456,925,000 | ||||||
| Reversal of valuation allowance | ¥ 0 | ¥ 147,630,000 | ¥ 61,722,000 | |||||||