Stock-Based Compensation (Detail) - (Table 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended	15 Months Ended
Sep. 30, 2012	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Proceeds from stock options exercised	$ 2,040	$ 6,991	$ 4,005	$ 520
Intrinsic value of stock options exercised	$ 4,213	$ 12,445	$ 8,861	$ 1,062

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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+ Details