Retirement Plans - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure
Accumulated other comprehensive income (loss), prior service cost expected to be recognized in 2018	$ 100
Fair value of pension plans assets totaled	325,800
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
Accumulated other comprehensive income (loss), prior service cost expected to be recognized in 2018	$ (100)
Discount rate utilized to determine future pension obligations	3.40%	3.90%	3.90%
Contribution to defined benefit pension plans	$ 557	$ 687
United States Plans
Defined Benefit Plan Disclosure
Percentage of expected return on plan assets assumption	4.00%
Discount rate utilized to determine future pension obligations	3.40%	3.90%
Fair value of pension plans assets totaled	$ 324,500
Contribution to defined benefit pension plans	1,900	$ 1,900
Contribution to defined benefit pension plans in 2018	1,900
Taiwan Defined Benefit Pension Plan
Defined Benefit Plan Disclosure
Fair value of pension plans assets totaled	1,300
U.S. Supplemental Executive Defined Benefit Pension Plan
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans	2,600	2,600
Contribution to defined benefit pension plans in 2018	2,500
Non-United States Subsidiaries
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans	900	900
Contribution to defined benefit pension plans in 2018	900
United States Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Accumulated benefit obligation for defined benefit pension plans	$ 354,300	$ 342,900
Percentage of expected return on plan assets assumption	4.00%	4.80%	4.80%
Discount rate utilized to determine future pension obligations	3.40%	3.90%
Fair value of pension plans assets totaled	$ 324,506	$ 307,304	$ 298,404
Contribution to defined benefit pension plans	4,462	4,489
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Accumulated benefit obligation for defined benefit pension plans	$ 34,700	$ 56,600
Percentage of expected return on plan assets assumption	2.00%	2.00%	2.60%
Discount rate utilized to determine future pension obligations	1.80%	1.80%
Fair value of pension plans assets totaled	$ 1,307	$ 27,571	$ 28,141
Contribution to defined benefit pension plans	$ 883	$ 867

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(ii)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(iv)(01)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

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