Employee Benefits - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Percentage of active employees with pension and/or other retirement benefit plans covered	33.33%
Percentage of matching contribution if compensation percentage below low range	100.00%
Matching participant's contribution, percentage on compensation	4.00%
Percentage of matching contribution if compensation percentage between high range and low range	75.00%
Matching participant's contribution, percentage on compensation, range low	4.00%
Matching participant's contribution, percentage on compensation, range high	8.00%
Percentage of employees eligible to accrue benefits under the defined plan	50.00%
Matching participant's contribution, average percentage on compensation	6.00%
Retirement liabilities	$ 354,333,000	$ 238,225,000
Capital in excess of par value related to Deferred Compensation Plan	19,000,000	15,100,000
Total cash surrender value of life insurance contracts	42,378,000	56,292,000
1% increase in accumulated postretirement benefit obligation	6,900,000
1% increase in postretirement expense	300,000
1% decrease in accumulated postretirement benefit obligation	6,700,000
1% decrease in postretirement expense	300,000
Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefits Paid	6,945,000	5,314,000
U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Retirement liabilities	119,791,000	91,930,000
Contribution to the plans	23,707,000	33,520,000
Defined Benefit Plan, Benefits Paid	27,341,000	26,157,000
U.S. Pension Plans [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities		40.00%
U.S. Pension Plans [Member] \| Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in equity securities		60.00%
Non-U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Retirement liabilities	113,103,000	32,315,000
Contribution to the plans	20,282,000	19,377,000
Defined Benefit Plan, Benefits Paid	32,134,000	27,571,000
Non-U.S. Pension Plans [Member] \| Alternative and other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in alternative investments, minimum	5.00%
Target percentage of investment in alternative investments, maximum	10.00%
Non-U.S. Pension Plans [Member] \| Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in alternative investments, minimum	5.00%
Target percentage of investment in alternative investments, maximum	20.00%
Non-U.S. Pension Plans [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in alternative investments, minimum	20.00%
Target percentage of investment in alternative investments, maximum	40.00%
Non-U.S. Pension Plans [Member] \| Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target percentage of investment in alternative investments, minimum	40.00%
Target percentage of investment in alternative investments, maximum	60.00%
Qualified U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to the plans	20,000,000
Non-Qualified U.S. Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit payments	3,700,000
Deferred Compensation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Retirement liabilities	$ 33,900,000	$ 29,700,000

Portion of Deferred Compensation Plan to be paid out in shares.

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Defined contribution plan, matching participant contribution, average percentage on compensation

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Defined contribution plan matching participant contribution percentage on compensation range

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Defined contribution plan, matching participant contribution, percentage on compensation, range high

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Defined contribution plan, matching participant contribution, percentage on compensation, range low

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Defined contribution plan, percentage of matching contribution if compensation percentage below low range

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Non-Qualified Plan, Benefits Paid

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Percentage of Active Employees with Pension and or Other Retirement Benefit Plans Covered

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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The increase in the fair value of plan assets from contributions made by the employer.

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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Target allocation of investments of this type to total plan assets presented on a weighted average basis.

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Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

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Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

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This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

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