Incentive Compensation Plans - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, number of shares authorized	2,150,000
Share-based compensation, number of shares available for grant	678,318
Share-based compensation options expiration period	10 years
Proceeds from stock option exercise	$ 1,300,000	$ 375,000	$ 466,000
Tax benefit realized from stock options exercised	335,000	172,000	143,000
Closing stock price	$ 36.77
Aggregate intrinsic value of outstanding in money stock options	7,000,000
Aggregate intrinsic value of outstanding exercisable in money stock options	6,200,000
Aggregate intrinsic value of stock options exercised	1,600,000	549,000	560,000
Total fair value of share awards vested	1,500,000	2,100,000	1,300,000
Share based compensation expense	1,600,000	1,600,000	1,800,000
Tax benefit associated with share based compensation expense recognized	577,000	563,000	420,000
Unrecognized share based compensation expense related to non vested stock awards	3,000,000
Weighted average period over which unrecognized expense expected to be recognized	2 years 9 months 18 days
Weighted average fair value of stock options granted	$ 824,000,000,000	$ 3,100,000	$ 1,600,000
Cash Incentive plans, expense	4,000,000	6,800,000	5,000,000
Cost of products sold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash Incentive plans, expense	3,900,000	4,500,000	2,700,000
Employee Stock Purchase Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, number of shares authorized	200,000
Employee stock purchase plan, percentage of total earning can be withheld	10.00%
Employee stock purchase plan, frequency of purchase	6 months
Employee stock purchase plan, percentage of purchase price of stock	85.00%
Employee stock purchase plan, shares issued	141,062
Employee Stock Purchase Plans \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase plan, number of shares that can be purchased by each employee six-month	100
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period over which unrecognized expense expected to be recognized	2 years 10 months 24 days
Number of shares granted to employees	35,000
Fair value per share of stocks granted to employees	$ 35.26
Unrecognized compensation cost related to non-vested time-based restricted common stock	$ 1,200,000
Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation options vesting period	3 years
Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation options vesting period	4 years

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Percentage of Employee Compensation Contributed into Share Purchase Plan, Maximum

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Percentage of Purchase Price Per Share

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Share Based Compensation Arrangement By Share Based Payment Award, Employee Investment Shares Purchase

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Share Based Compensation Arrangement by Share Based Payment Award Employee Stock Purchase Plan Each Offering Period

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Share Based Compensation Arrangement by Share Based Payment Award, Options, Expiration Term

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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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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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Price of a single share of a number of saleable stocks of a company.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Tax benefits realized from the exercise of stock options resulting in reductions in the entity's income taxes, which increases net cash provided by operating activities.

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