Share based compensation - Options Exercised (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Share based compensation | |||
| Option Exercised (in shares) | 5,334,936 | 1,142,904 | 63,192 |
| Intrinsic value of stock options exercised | $ 6,727,000 | $ 1,522,000 | $ 40,000 |
| Proceeds from exercise of stock options | 3,037,000 | 401,000 | 17,000 |
| Tax benefit from stock option exercises | $ 1,325,000 | $ 73,000 | $ 8,000 |
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- Definition Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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