Schedule of Net Periodic Pension and Postretirement (income) Cost (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
Service cost	$ 59	$ 75	$ 67
Interest cost	335	342	437
Amortization of prior service cost	(598)	(598)	(599)
Net actuarial (gain) loss	(1,255)	(2,025)	83
Total net periodic pension cost (income)	(1,459)	(2,206)	(12)
Prior service cost	598	598	599
Total recognized in other comprehensive income	598	598	599
Total recognized in net periodic pension cost (income) and other comprehensive income	(861)	(1,608)	587
Defined Benefit Pension Plans \| United States
Defined Benefit Plan Disclosure
Service cost	2,218	2,393	2,102
Interest cost	12,875	11,318	13,713
Expected return on plan assets	(12,500)	(13,632)	(15,248)
Amortization of prior service cost	135	164	232
Net actuarial (gain) loss	43,168	(7,063)	15,458
Total net periodic pension cost (income)	45,896	(6,820)	16,257
Prior service cost	(135)	(164)	(232)
Total recognized in other comprehensive income	(135)	(164)	(232)
Total recognized in net periodic pension cost (income) and other comprehensive income	45,761	(6,984)	16,025
Defined Benefit Pension Plans \| Foreign
Defined Benefit Plan Disclosure
Service cost	897	1,034	686
Interest cost	1,837	1,948	1,956
Expected return on plan assets	(868)	(959)	(698)
Net actuarial (gain) loss	4,651	(1,252)	7,779
Total net periodic pension cost (income)	6,517	771	9,723
Total recognized in net periodic pension cost (income) and other comprehensive income	$ 6,517	$ 771	$ 9,723

Defined benefit plan, recognized in net periodic pension cost and other comprehensive income total.

No definition available.

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- Definition

The amount of gains or losses recognized in net periodic benefit cost.

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- Definition

Amount before tax, after reclassification adjustments, of prior service cost (credit) that has not been recognized in the income statement.

+ References

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512136

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512171

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ 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 (h)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Service Cost (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (i-k)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

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