Summary of Significant Accounting Policies	12 Months Ended
Dec. 31, 2012
Summary of Significant Accounting Policies	(1) SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations Entegris, Inc. (Entegris or the Company) is a leading provider of products and services that purify, protect and transport the critical materials used in key technology-driven industries, primarily the semiconductor and related industries. Principles of Consolidation The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries. Intercompany profits, transactions and balances have been eliminated in consolidation. Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States requires management to make judgments, estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. On an ongoing basis, Entegris evaluates its estimates, including those related to receivables, inventories, property, plant and equipment, intangible assets, accrued expenses, income taxes and share-based compensation, among others. Actual results could differ from those estimates. Concentrations of Suppliers Certain materials included in the Company’s products are obtained from a single source or a limited group of suppliers. Although the Company seeks to reduce dependence on those sole and limited source suppliers, the partial or complete loss of these sources could have at least a temporary adverse effect on the Company’s results of operations. Furthermore, a significant increase in the price of one or more of these components could adversely affect the Company’s results of operations. Cash and Cash Equivalents Cash and cash equivalents include cash on hand and highly liquid debt securities with original maturities of three months or less, which are valued at cost which approximates fair value. Allowance for Doubtful Accounts An allowance for uncollectible trade receivables is estimated based on a combination of write-off history, aging analysis and any specific, known troubled accounts. The Company maintains an allowance for doubtful accounts that management believes is adequate to cover expected losses on trade receivables. Inventories Inventories are stated at the lower of cost or market. Cost is determined by the first-in, first-out (FIFO) method. Property, Plant, and Equipment Property, plant and equipment are carried at cost and are depreciated on the straight-line method over the estimated useful lives of the assets. When assets are retired or disposed of, the cost and related accumulated depreciation are removed from the accounts, and gains or losses are recognized in the same period. Maintenance and repairs are expensed as incurred; significant additions and improvements are capitalized. Long-lived assets, including property, plant and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or group of asset(s) may not be recoverable based on estimated future undiscounted cash flows. The amount of impairment, if any, is measured as the difference between the net book value and the estimated fair value of the asset(s). Investments The Company’s nonmarketable investments are accounted for under either the cost or equity method of accounting, as appropriate. All nonmarketable investments are periodically reviewed to determine whether declines, if any, in fair value below cost basis are other-than-temporary. If the decline in fair value is determined to be other-than-temporary, an impairment loss is recorded and the investment written down to a new cost basis. Fair Value of Financial Instruments The carrying value of cash equivalents, accounts receivable and accounts payable approximates fair value due to the short maturity of those instruments. Intangible Assets Amortizable intangible assets include, among other items, patents, unpatented and other developed technology and customer-based intangibles, and are amortized using the straight-line method over their respective estimated useful lives of 3 to 15 years. The Company reviews intangible assets, along with other long-lived assets, for impairment if changes in circumstances or the occurrence of events suggest the remaining value may not be recoverable. Derivative Financial Instruments The Company records derivatives as assets or liabilities on the balance sheet and measures such instruments at fair value. Changes in fair value of derivatives are recorded each period in current results of operations or other comprehensive income. The Company periodically enters into forward foreign currency contracts to reduce exposures relating to rate changes in certain foreign currencies. Certain exposures to credit losses related to counterparty nonperformance exist. However, the Company does not anticipate nonperformance by the counterparties since they are large, well-established financial institutions. None of these derivatives is accounted for as a hedge transaction. Accordingly, changes in the fair value of forward foreign currency contracts are recorded as other (income) expense, net in the Company’s statement of operations. The fair values of the Company’s derivative financial instruments are based on prices quoted by financial institutions for these instruments. The Company had no net exposure to any forward contracts at December 31, 2012 and December 31, 2011. Foreign Currency Translation Assets and liabilities of foreign subsidiaries are generally translated from foreign currencies into U.S. dollars at period-end exchange rates, and the resulting gains and losses arising from translation of net assets located outside the U.S. are recorded as a cumulative translation adjustment, a component of accumulated other comprehensive income (loss) in the consolidated balance sheets. Income statement amounts are translated at the weighted average exchange rates for the year. Translation adjustments are not adjusted for income taxes as substantially all translation adjustments relate to permanent investments in non-U.S. subsidiaries. Gains and losses resulting from foreign currency transactions are included in other income, net in the consolidated statements of operations. Revenue Recognition Revenue and the related cost of sales are generally recognized upon shipment of the products. Revenue for product sales is recognized upon delivery, when persuasive evidence of an arrangement exists, when title and risk of loss have been transferred to the customer, collectability is reasonably assured, and pricing is fixed or determinable. Shipping and handling fees related to sales transactions are billed to customers and are recorded as sales revenue. The Company sells its products throughout the world primarily to companies in the microelectronics industry. The Company performs continuing credit evaluations of its customers and generally does not require collateral. Letters of credit may be required from its customers in certain circumstances. The Company provides for estimated returns when the revenue is recorded based on historical and current trends in both sales and product returns. The Company collects various sales and value-added taxes on certain product and service sales that are accounted for on a net basis. Shipping and handling costs Shipping and handling costs incurred are recorded in cost of sales in the consolidated statements of operations. Engineering, research and development expenses Engineering, research and development expenses costs are expensed as incurred. Share-based Compensation The Company measures the cost of employee services received in exchange for the award of equity instruments based on the fair value of the award at the date of grant. The cost is recognized over the period during which an employee is required to provide services in exchange for the award. Compensation expense is based on the grant date fair value. Because share-based compensation expense recognized in the consolidated statements of operations for the years ended December 31, 2012, 2011 and 2010 is based on awards ultimately expected to vest, it has been reduced for expected forfeitures which are estimated at the time of grant with such estimates revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Company recognizes deferred tax assets to the extent that it believes these assets are more likely than not to be realized. A valuation allowance is recorded to reduce deferred tax assets when it is more likely than not that the Company would not be able to realize all or part of its deferred tax assets. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. If the Company determines that it would be able to realize its deferred tax assets in the future in excess of their net recorded amount, the Company would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes. The Company’s policy for recording interest and penalties associated with audits and unrecognized tax benefits is to record such items as a component of income before taxes. Penalties are recorded in other (income) expense, net and interest to be paid or received is recorded in interest expense or interest income, respectively, in the statement of operations. Comprehensive Income Comprehensive income represents the change in equity resulting from items other than shareholder investments and distributions. The Company’s foreign currency translation adjustments and minimum pension liability adjustments are included in accumulated other comprehensive income. Comprehensive income and the components of accumulated other comprehensive income are presented in the accompanying consolidated statements of equity and comprehensive income. Recent Accounting Pronouncements In June 2011, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2011-05, Presentation of Comprehensive Income, which requires entities to present reclassification adjustments included in other comprehensive income on the face of the financial statements and allows entities to present the total of comprehensive income, the components of net income and the components of other comprehensive income either in a single continuous statement of comprehensive income or in two separate but consecutive statements. It also eliminates the option for entities to present the components of other comprehensive income as part of the statement of changes in stockholders’ equity. ASU No. 2011-05 was effective for the Company in the first quarter of 2012. Adoption of this ASU relates to the presentation of financial information and had no effect on the Company’s consolidated financial position or results of operations.

(1) SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Nature of Operations Entegris, Inc. (Entegris or the Company) is a leading provider of products and services that purify, protect and transport the critical materials used in key technology-driven industries, primarily the semiconductor and related industries.

Principles of Consolidation The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries. Intercompany profits, transactions and balances have been eliminated in consolidation.

Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States requires management to make judgments, estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. On an ongoing basis, Entegris evaluates its estimates, including those related to receivables, inventories, property, plant and equipment, intangible assets, accrued expenses, income taxes and share-based compensation, among others. Actual results could differ from those estimates.

Concentrations of Suppliers Certain materials included in the Company’s products are obtained from a single source or a limited group of suppliers. Although the Company seeks to reduce dependence on those sole and limited source suppliers, the partial or complete loss of these sources could have at least a temporary adverse effect on the Company’s results of operations. Furthermore, a significant increase in the price of one or more of these components could adversely affect the Company’s results of operations.

Cash and Cash Equivalents Cash and cash equivalents include cash on hand and highly liquid debt securities with original maturities of three months or less, which are valued at cost which approximates fair value.

Allowance for Doubtful Accounts An allowance for uncollectible trade receivables is estimated based on a combination of write-off history, aging analysis and any specific, known troubled accounts. The Company maintains an allowance for doubtful accounts that management believes is adequate to cover expected losses on trade receivables.

Inventories Inventories are stated at the lower of cost or market. Cost is determined by the first-in, first-out (FIFO) method.

Property, Plant, and Equipment Property, plant and equipment are carried at cost and are depreciated on the straight-line method over the estimated useful lives of the assets. When assets are retired or disposed of, the cost and related accumulated depreciation are removed from the accounts, and gains or losses are recognized in the same period. Maintenance and repairs are expensed as incurred; significant additions and improvements are capitalized. Long-lived assets, including property, plant and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or group of asset(s) may not be recoverable based on estimated future undiscounted cash flows. The amount of impairment, if any, is measured as the difference between the net book value and the estimated fair value of the asset(s).

Investments The Company’s nonmarketable investments are accounted for under either the cost or equity method of accounting, as appropriate. All nonmarketable investments are periodically reviewed to determine whether declines, if any, in fair value below cost basis are other-than-temporary. If the decline in fair value is determined to be other-than-temporary, an impairment loss is recorded and the investment written down to a new cost basis.

Fair Value of Financial Instruments The carrying value of cash equivalents, accounts receivable and accounts payable approximates fair value due to the short maturity of those instruments.

Intangible Assets Amortizable intangible assets include, among other items, patents, unpatented and other developed technology and customer-based intangibles, and are amortized using the straight-line method over their respective estimated useful lives of 3 to 15 years. The Company reviews intangible assets, along with other long-lived assets, for impairment if changes in circumstances or the occurrence of events suggest the remaining value may not be recoverable.

Derivative Financial Instruments The Company records derivatives as assets or liabilities on the balance sheet and measures such instruments at fair value. Changes in fair value of derivatives are recorded each period in current results of operations or other comprehensive income.

The Company periodically enters into forward foreign currency contracts to reduce exposures relating to rate changes in certain foreign currencies. Certain exposures to credit losses related to counterparty nonperformance exist. However, the Company does not anticipate nonperformance by the counterparties since they are large, well-established financial institutions. None of these derivatives is accounted for as a hedge transaction. Accordingly, changes in the fair value of forward foreign currency contracts are recorded as other (income) expense, net in the Company’s statement of operations. The fair values of the Company’s derivative financial instruments are based on prices quoted by financial institutions for these instruments. The Company had no net exposure to any forward contracts at December 31, 2012 and December 31, 2011.

Foreign Currency Translation Assets and liabilities of foreign subsidiaries are generally translated from foreign currencies into U.S. dollars at period-end exchange rates, and the resulting gains and losses arising from translation of net assets located outside the U.S. are recorded as a cumulative translation adjustment, a component of accumulated other comprehensive income (loss) in the consolidated balance sheets. Income statement amounts are translated at the weighted average exchange rates for the year. Translation adjustments are not adjusted for income taxes as substantially all translation adjustments relate to permanent investments in non-U.S. subsidiaries. Gains and losses resulting from foreign currency transactions are included in other income, net in the consolidated statements of operations.

Revenue Recognition Revenue and the related cost of sales are generally recognized upon shipment of the products. Revenue for product sales is recognized upon delivery, when persuasive evidence of an arrangement exists, when title and risk of loss have been transferred to the customer, collectability is reasonably assured, and pricing is fixed or determinable. Shipping and handling fees related to sales transactions are billed to customers and are recorded as sales revenue.

The Company sells its products throughout the world primarily to companies in the microelectronics industry. The Company performs continuing credit evaluations of its customers and generally does not require collateral. Letters of credit may be required from its customers in certain circumstances. The Company provides for estimated returns when the revenue is recorded based on historical and current trends in both sales and product returns.

The Company collects various sales and value-added taxes on certain product and service sales that are accounted for on a net basis.

Shipping and handling costs Shipping and handling costs incurred are recorded in cost of sales in the consolidated statements of operations.

Engineering, research and development expenses Engineering, research and development expenses costs are expensed as incurred.

Share-based Compensation The Company measures the cost of employee services received in exchange for the award of equity instruments based on the fair value of the award at the date of grant. The cost is recognized over the period during which an employee is required to provide services in exchange for the award. Compensation expense is based on the grant date fair value. Because share-based compensation expense recognized in the consolidated statements of operations for the years ended December 31, 2012, 2011 and 2010 is based on awards ultimately expected to vest, it has been reduced for expected forfeitures which are estimated at the time of grant with such estimates revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates.

Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date.

The Company recognizes deferred tax assets to the extent that it believes these assets are more likely than not to be realized. A valuation allowance is recorded to reduce deferred tax assets when it is more likely than not that the Company would not be able to realize all or part of its deferred tax assets. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. If the Company determines that it would be able to realize its deferred tax assets in the future in excess of their net recorded amount, the Company would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes.

The Company’s policy for recording interest and penalties associated with audits and unrecognized tax benefits is to record such items as a component of income before taxes. Penalties are recorded in other (income) expense, net and interest to be paid or received is recorded in interest expense or interest income, respectively, in the statement of operations.

Comprehensive Income Comprehensive income represents the change in equity resulting from items other than shareholder investments and distributions. The Company’s foreign currency translation adjustments and minimum pension liability adjustments are included in accumulated other comprehensive income. Comprehensive income and the components of accumulated other comprehensive income are presented in the accompanying consolidated statements of equity and comprehensive income.

Recent Accounting Pronouncements

In June 2011, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2011-05, Presentation of Comprehensive Income, which requires entities to present reclassification adjustments included in other comprehensive income on the face of the financial statements and allows entities to present the total of comprehensive income, the components of net income and the components of other comprehensive income either in a single continuous statement of comprehensive income or in two separate but consecutive statements. It also eliminates the option for entities to present the components of other comprehensive income as part of the statement of changes in stockholders’ equity. ASU No. 2011-05 was effective for the Company in the first quarter of 2012. Adoption of this ASU relates to the presentation of financial information and had no effect on the Company’s consolidated financial position or results of operations.