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Basic and Diluted Net Earnings Per Share - Additional Information (Detail)
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6 Months Ended | ||
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Jun. 30, 2013
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Jun. 30, 2012
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Dec. 31, 2012
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| Earnings Per Share [Abstract] | |||
| Options to purchase Class A common stock | 2,410,330 | 2,106,674 | 1,927,099 |
| Dilutive shares | 887,219 | 213,476 | |
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- Details
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- Definition
Number of options outstanding, including both vested and non-vested options. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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