Reconciliation of Total Segment Profit to Operating Income (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment profit	$ 228,500entg_TotalSegmentProfit	$ 148,944entg_TotalSegmentProfit	$ 165,809entg_TotalSegmentProfit
Charge for fair value write-up of acquired inventory sold	48,586entg_AmortizationofInventoryStepup	0entg_AmortizationofInventoryStepup	0entg_AmortizationofInventoryStepup
Amortization of intangibles	37,067us-gaap_AmortizationOfIntangibleAssets	9,347us-gaap_AmortizationOfIntangibleAssets	9,594us-gaap_AmortizationOfIntangibleAssets
Contingent consideration fair value adjustment	(1,282)	(1,813)	0
Unallocated general and administrative expenses	122,775	47,173	56,771
Operating income	21,354us-gaap_OperatingIncomeLoss	94,237us-gaap_OperatingIncomeLoss	99,444us-gaap_OperatingIncomeLoss
Other expense (income), net	2,727us-gaap_OtherNonoperatingIncomeExpense	(1,794)us-gaap_OtherNonoperatingIncomeExpense	(249)us-gaap_OtherNonoperatingIncomeExpense
(Loss) income before income tax (benefit) expense and equity in net loss (income) of affiliates	(13,392)	96,195	99,703
Interest expense	33,355us-gaap_InterestExpense	153us-gaap_InterestExpense	271us-gaap_InterestExpense
Interest income	$ 1,336us-gaap_InterestIncomeOther	$ 317us-gaap_InterestIncomeOther	$ 281us-gaap_InterestIncomeOther

Amortization of Inventory Step-up

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- Definition

Total segment profit

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No definition available.

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- Definition

General and administrative expenses not allocated to segment profit of company's business segments

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

Amount of interest income earned from interest bearing assets not separately disclosed.

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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- Definition

The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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