Share based compensation - Options Exercised (Details) - USD ($) $ in Thousands |
6 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Jun. 30, 2015 |
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| Share based compensation | ||||
| Option Exercised (in shares) | 0 | 1,142,904 | 63,192 | 0 |
| Intrinsic value of stock options exercised | $ 1,522 | $ 40 | ||
| Proceeds from exercise of stock options | 401 | 17 | ||
| Tax benefit from stock option exercises | $ 0 | $ 73 | $ 8 | $ 0 |
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- Definition Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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