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Retirement plans (Details) (USD $)
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12 Months Ended | ||
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Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2010
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| Compensation and Retirement Disclosure [Abstract] | |||
| Maximum employer annual contribution per employee, percent | 4.50% | ||
| Contributions to plan | $ 116,850 | $ 115,120 | $ 111,100 |
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- Details
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- Definition
The amount of the cost recognized during the period for defined contribution plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. No definition available.
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