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Stock Option Activity and Weighted Average Exercise Price (Detail) (USD $)
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12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2010
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Stock Option Plans
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| Outstanding Shares | |||
| Beginning Balance | 4,682,737 | 4,308,812 | 2,837,800 |
| Granted | 570,700 | 1,276,500 | 1,615,812 |
| Exercised | (861,397) | (865,875) | (6,000) |
| Forfeited | (61,630) | (36,700) | (138,800) |
| Ending Balance | 4,330,410 | 4,682,737 | 4,308,812 |
| Vested or expected to vest at end of period | 4,330,410 | ||
| Options exercisable at end of period | 864,558 | ||
| Weighted-Average Exercise Price | |||
| Beginning Balance | $ 29.45 | $ 20.54 | $ 16.89 |
| Granted | $ 66.19 | $ 50.52 | $ 26.81 |
| Exercised | $ 22.54 | $ 16.30 | $ 24.25 |
| Forfeited | $ 40.95 | $ 26.38 | $ 18.79 |
| Ending Balance | $ 35.50 | $ 29.45 | $ 20.54 |
| Vested or expected to vest at end of period | $ 35.50 | ||
| Options exercisable at end of period | $ 21.69 | ||
|
Omnibus Incentive Plan
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| Outstanding Shares | |||
| Beginning Balance | 1,098,546 | 2,473,760 | 6,439,246 |
| Exercised | (744,974) | (1,373,414) | (3,951,986) |
| Forfeited | (1,800) | (13,500) | |
| Ending Balance | 353,572 | 1,098,546 | 2,473,760 |
| Vested or expected to vest at end of period | 353,572 | ||
| Options exercisable at end of period | 353,572 | ||
| Weighted-Average Exercise Price | |||
| Beginning Balance | $ 25.08 | $ 23.36 | $ 19.15 |
| Exercised | $ 25.84 | $ 21.98 | $ 16.50 |
| Forfeited | $ 24.27 | $ 21.49 | |
| Ending Balance | $ 23.47 | $ 25.08 | $ 23.36 |
| Vested or expected to vest at end of period | $ 23.47 | ||
| Options exercisable at end of period | $ 23.47 | ||
|
Non Employee Directors, Plan
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| Outstanding Shares | |||
| Beginning Balance | 80,000 | 104,000 | 176,000 |
| Granted | 8,000 | ||
| Exercised | (64,000) | (16,000) | (72,000) |
| Forfeited | (8,000) | ||
| Ending Balance | 16,000 | 80,000 | 104,000 |
| Vested or expected to vest at end of period | 16,000 | ||
| Options exercisable at end of period | 16,000 | ||
| Weighted-Average Exercise Price | |||
| Beginning Balance | $ 23.52 | $ 21.91 | $ 23.03 |
| Exercised | $ 22.62 | $ 18.14 | $ 24.65 |
| Forfeited | $ 13.35 | ||
| Ending Balance | $ 27.10 | $ 23.52 | $ 21.91 |
| Vested or expected to vest at end of period | $ 27.10 | ||
| Options exercisable at end of period | $ 27.10 | ||