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Income taxes (Details) (USD $)
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3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2012
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Jun. 30, 2011
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Jun. 30, 2012
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Jun. 30, 2011
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| Income taxes | ||||
| Windfall tax benefits from stock option exercises | $ 2,400,000 | |||
| Income tax expense | 709,000 | 312,000 | 1,367,000 | 791,000 |
| Effective tax rate (as a percent) | 28.60% | 20.50% | ||
| Deferred tax assets | $ 6,449,000 | $ 6,449,000 | ||
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- Definition
Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Windfall tax benefits recognized from the exercise of stock options resulting in a reduction of the entity's income tax payable, with a corresponding increase in additional paid-in capital. No definition available.
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