Accumulated Other Comprehensive Income (Loss) - Summary of Amounts Reclassifications Out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017		Jun. 30, 2018	Jun. 30, 2017
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income Before Provision for Income Taxes		$ 42,497	$ 37,063	[1]	$ 80,161	$ 81,393	[1]
Tax benefit		(9,574)	(9,167)		(16,522)	(21,585)
Cost of Sales	[2]	430,586	405,113		840,351	781,263
Defined Benefit Pension Plan Adjustments [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Amortization of defined benefit pension actuarial losses	[3],[4]	(992)	(883)		(1,986)	(1,763)
Tax benefit	[3]	240	316		481	631
Income applicable to common stock	[3]	(752)	(567)		(1,505)	(1,132)
Cash Flow Hedge Adjustments [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income Before Provision for Income Taxes	[3]	2	3		5	5
Income applicable to common stock	[3]	2	3		5	5
Cash Flow Hedge Adjustments [Member] | Foreign exchange contracts [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Cost of Sales	[3]	2	3		5	5
Accumulated Other Comprehensive Income (Loss) [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income applicable to common stock	[3]	$ (750)	$ (564)		$ (1,500)	$ (1,127)

[1] The 2017 data has been immaterially changed from the amounts originally reported as a result of the Company’s first quarter 2018 adoption of ASU No. 2017-7, Compensation-Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost.

[2] The 2017 amounts for the noted line items have been immaterially changed from the amounts originally reported as a result of the Company’s first quarter 2018 adoption of Accounting Standards Update (ASU) No. 2017-7, Compensation –Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost.

[3] Amounts in parentheses denote expense to statement of income.

[4] This component of accumulated other comprehensive income is included in the computation of net periodic benefit cost (see Note 8 for additional details).