Stock-Based Compensation Plans - Schedule of Outstanding Options into Two Ranges, Based on Exercise Prices (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices remaining contractual life, outstanding	4 years 4 months 24 days
Range of exercise prices shares, outstanding	278
Range of exercise prices weighted average exercise price, outstanding	$ 42
Range of exercise prices shares, exercisable	216
Options Exercisable, Weighted Avg. Exercise Price	$ 41
Outstanding Options with Range Based Exercise Prices Set One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 12.22
Exercise price range, upper range limit	$ 45.70
Range of exercise prices remaining contractual life, outstanding	3 years 7 months 6 days
Range of exercise prices shares, outstanding	128
Range of exercise prices weighted average exercise price, outstanding	$ 35
Range of exercise prices shares, exercisable	119
Options Exercisable, Weighted Avg. Exercise Price	$ 34
Outstanding Options with Range Based Exercise Prices Set Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 46.93
Exercise price range, upper range limit	$ 50.30
Range of exercise prices remaining contractual life, outstanding	5 years
Range of exercise prices shares, outstanding	150
Range of exercise prices weighted average exercise price, outstanding	$ 48
Range of exercise prices shares, exercisable	97
Options Exercisable, Weighted Avg. Exercise Price	$ 48