SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
Sep. 30, 2016
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES EPAM Systems, Inc. (the “Company” or “EPAM”) is a global provider of software product engineering, technology consulting and digital expertise to clients located around the world, primarily in North America, Europe, Asia and the CIS region. The Company has expertise in various industries, including software and hi-tech, financial services, media and entertainment, travel and hospitality, retail and distribution, and life sciences and healthcare. The Company is incorporated in Delaware with headquarters in Newtown, PA. EPAM serves clients worldwide utilizing an award-winning global delivery platform and its locations in over 25 countries across North America, Europe, Asia and Australia. Basis of Presentation —The accompanying unaudited condensed consolidated financial statements of EPAM have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and Article 10 of Regulation S-X under the Securities Exchange Act of 1934, as amended. The condensed consolidated financial statements include the financial statements of EPAM Systems, Inc. and its subsidiaries with all intercompany balances and transactions eliminated. These unaudited condensed consolidated financial statements and accompanying notes should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2015 included in its Annual Report on Form 10-K. The preparation of these condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates, and such differences may be material to the condensed consolidated financial statements. Operating results for the interim periods are not necessarily indicative of results that may be expected to occur for the entire year. In our opinion, all adjustments considered necessary for a fair presentation of the accompanying unaudited condensed consolidated financial statements have been included, and all adjustments are of a normal and recurring nature. Reclassification — During the first quarter of 2016, the Company revised the classification of certain health insurance premium and other employee fringe benefit expenses between the cost of revenues and selling, general and administrative expenses line items on the condensed consolidated statements of income and comprehensive income. The effect of this reclassification had no impact on total income from operations for the three and nine months ended September 30, 2016. Revenue Recognition — The Company recognizes revenue when the following criteria are met: (1) persuasive evidence of an arrangement exists; (2) delivery has occurred; (3) the sales price is fixed or determinable; and (4) collectability is reasonably assured. Determining whether and when some of these criteria have been satisfied often involves assumptions and judgments that can have a significant impact on the timing and amount of revenue reported. The Company derives its revenues from a variety of service offerings, which represent specific competencies of its IT professionals. Contracts for these services have different terms and conditions based on the scope, deliverables, and complexity of the engagement, which require management to make judgments and estimates in determining the appropriate revenue recognition. Fees for these contracts may be in the form of time-and-materials or fixed-price arrangements. If there is an uncertainty about the project completion or receipt of payment for the services, revenue is deferred until the uncertainty is sufficiently resolved. At the time revenue is recognized, the Company provides for any contractual deductions and reduces the revenue accordingly. The Company reports gross reimbursable “out-of-pocket” expenses incurred as both revenues and cost of revenues in the condensed consolidated statements of income and comprehensive income. The Company defers amounts billed to its clients for revenues not yet earned. Such amounts are anticipated to be recorded as revenues when services are performed in subsequent periods. Unbilled revenue is recorded when services have been provided but billed subsequent to the period end in accordance with the contract terms. Fair Value of Financial Instruments — The Company makes assumptions about fair values of its financial assets and liabilities in accordance with the Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 820, “Fair Value Measurement”, and utilizes the following fair value hierarchy in determining inputs used for valuation: Level 1 — Quoted prices for identical assets or liabilities in active markets. Level 2 — Inputs other than quoted prices within Level 1 that are observable either directly or indirectly, including quoted prices in markets that are not active, quoted prices in active markets for similar assets or liabilities, and observable inputs other than quoted prices such as interest rates or yield curves. Level 3 — Unobservable inputs reflecting our view about the assumptions that market participants would use in pricing the asset or liability. Where the fair values of financial assets and liabilities recorded in the condensed consolidated balance sheets cannot be derived from an active market, they are determined using a variety of valuation techniques. These valuation techniques include a net present value technique, comparison to similar instruments with market observable inputs, option pricing models and other relevant valuation models. To the extent possible, observable market data is used as inputs into these models but when it is not feasible, a degree of judgment is required to establish fair values. The Company’s contingent liabilities measured at fair value on a recurring basis are comprised of performance-based awards issued to certain former owners of acquired businesses in exchange for future services and cash settled restricted stock units issued to employees. Performance-based awards issued to certain former owners of acquired businesses are valued using significant inputs that are not observable in the market, which are defined as Level 3 inputs according to fair value measurement accounting. The Company believes its estimates and assumptions are reasonable, however, there is significant judgment involved. Cash settled restricted stock units issued to employees are valued using the price of the Company's stock, a significant input that is observable in the market, which is defined as Level 1 input according to fair value measurement accounting. These changes in fair value could cause a material impact to, and volatility in the Company’s operating results. See Note 4 for disclosures related to fair value. Employee Loans — The Company issues employee housing loans in Belarus, relocation loans to assist employees with relocation needs in connection with intra-company transfers and loans for the purchase of automobiles in India. There are no loans issued to principal officers, directors, and their affiliates. The Company intends to hold all employee loans until their maturity. Interest income is reported using the effective interest method. Where applicable, loan origination fees, net of direct origination costs, are deferred and recognized in interest income over the life of the loan. On a quarterly basis, the Company reviews the aging of its loan portfolio and evaluates the ability of employees to repay their debt on schedule. Factors considered in the review include historical payment experience, reasons for payment delays and shortfalls, if any, as well as probability of collecting scheduled principal and interest payments. Since the initiation of the loan program there have not been material past due or non-accrual employee loans or write offs related to loan losses and, therefore, the Company determined that no allowance for loan losses is required. Employee Housing Loans — In 2012, the Board of Directors of the Company approved the Employee Housing Program (the “Housing Program”), which provides employees with loans to purchase housing in Belarus. The housing is sold directly to employees by independent third parties. The Housing Program was designed as a retention mechanism for the Company’s employees in Belarus and is available to full-time qualified employees who have been with the Company for at least three years. The aggregate maximum lending limit of the program is $10,000, with individual loans not exceeding $50. Loans issued under the Housing Program are denominated in U.S. dollars with a 5-year term and an interest rate of 7.5%. The housing loans are measured using the Level 3 inputs within the fair value hierarchy because they are valued using significant unobservable inputs. These housing loans are measured at fair value upon initial recognition through the market approach under ASC Topic 820, “Fair Value Measurement” and subsequently carried at amortized cost less allowance for loan losses, if any. Any difference between the carrying value and the fair value of a loan upon initial recognition is charged to expense. Employee Loans, Other — The Company issues short-term, non-interest bearing relocation loans to employees who have relocated within the company. In addition, the Company has in the past issued and may issue in the future a small number of interest bearing loans to employees for the purchase of automobiles. Such loans are issued to qualified employees with certain conditions attached. Due to the short term duration of these employee loans and high certainty of repayment, their carrying amount is a reasonable estimate of their fair value. Business Combinations — The Company accounts for its business combinations using the acquisition accounting method, which requires it to determine the fair value of net assets acquired and the related goodwill and other intangible assets in accordance with the FASB ASC Topic 805, “Business Combinations.” The Company identifies and attributes fair values and estimated lives to the intangible assets acquired and allocates the total cost of an acquisition to the underlying net assets based on their respective estimated fair values. Determining the fair value of assets acquired and liabilities assumed requires management’s judgment and involves the use of significant estimates, including projections of future cash inflows and outflows, discount rates, asset lives and market multiples. There are different valuation models for each component, the selection of which requires considerable judgment. These determinations will affect the amount of amortization expense recognized in future periods. The Company bases its fair value estimates on assumptions it believes are reasonable, but recognizes that the assumptions are inherently uncertain. If initial accounting for the business combination has not been completed by the end of the reporting period in which the business combination occurs, provisional amounts are reported for which the accounting is incomplete, with retrospective adjustment made to such provisional amounts during the measurement period to present new information about facts and circumstances that existed as of the acquisition date. All acquisition-related costs, other than the costs to issue debt or equity securities, are accounted for as expenses in the period in which they are incurred. Changes in fair value of contingent consideration arrangements that are not measurement period adjustments are recognized in earnings. Payments to settle contingent consideration, if any, are reflected in cash flows from financing activities and the changes in fair value are reflected in cash flows from operating activities in the Company’s condensed consolidated statements of cash flows. The acquired assets typically consist of customer relationships, trade names, non-competition agreements, and workforce and as a result, a substantial portion of the purchase price is usually allocated to goodwill and other intangible assets. Goodwill and Other Intangible Assets — Goodwill and intangible assets that have indefinite useful lives are accounted for in accordance with FASB ASC 350, “Intangibles - Goodwill and Other.” The Company conducts its evaluation of goodwill impairment at the reporting unit level on an annual basis during its fourth quarter, and more frequently if events or circumstances indicate that the carrying value of a reporting unit exceeds its fair value. A reporting unit is an operating segment or one level below. The Company does not have intangible assets that have indefinite useful lives. Intangible assets that have finite useful lives are amortized over their estimated useful lives on a straight-line basis. When facts and circumstances indicate potential impairment of amortizable intangible assets, the Company evaluates the recoverability of the asset’s carrying value, using estimates of future cash flows over the remaining asset life. The estimates of future cash flows attributable to intangible assets require significant judgment based on the Company’s historical and anticipated results. Any impairment loss is measured by the excess of carrying value over fair value. Stock-Based Compensation — The Company recognizes the cost of its stock-based incentive awards based on the fair value of the award at the date of grant net of estimated forfeitures. The cost is expensed evenly over the service period. The service period is the period over which the employee performs the related services, which is normally the same as the vesting period. Over time, the forfeiture assumption is adjusted to the actual forfeiture rate and such change may affect the timing of the total amount of expense recognized over the vesting period. Equity-based awards that do not require future service are expensed immediately. Equity-based awards that do not meet the criteria for equity classification are recorded as liabilities and adjusted to fair value at the end of each reporting period. Off-Balance Sheet Financial Instruments — The Company uses FASB ASC Topic 825, “Financial Instruments” to identify and disclose off-balance sheet financial instruments, which include credit instruments, such as commitments to make employee loans and related guarantees, standby letters of credit and certain guarantees issued under customer contracts. The face amount for these items represents the exposure to loss, before considering available collateral or the borrower’s ability to repay. Loss contingencies arising from off-balance sheet financial instruments are recorded as liabilities when the likelihood of loss is probable and an amount or range of loss can be reasonably estimated. The Company does not believe such matters exist that will have a material effect on the condensed consolidated financial statements.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

EPAM Systems, Inc. (the “Company” or “EPAM”) is a global provider of software product engineering, technology consulting and digital expertise to clients located around the world, primarily in North America, Europe, Asia and the CIS region. The Company has expertise in various industries, including software and hi-tech, financial services, media and entertainment, travel and hospitality, retail and distribution, and life sciences and healthcare.

The Company is incorporated in Delaware with headquarters in Newtown, PA. EPAM serves clients worldwide utilizing an award-winning global delivery platform and its locations in over 25 countries across North America, Europe, Asia and Australia.

Basis of Presentation —The accompanying unaudited condensed consolidated financial statements of EPAM have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and Article 10 of Regulation S-X under the Securities Exchange Act of 1934, as amended. The condensed consolidated financial statements include the financial statements of EPAM Systems, Inc. and its subsidiaries with all intercompany balances and transactions eliminated.

These unaudited condensed consolidated financial statements and accompanying notes should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2015 included in its Annual Report on Form 10-K. The preparation of these condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates, and such differences may be material to the condensed consolidated financial statements. Operating results for the interim periods are not necessarily indicative of results that may be expected to occur for the entire year. In our opinion, all adjustments considered necessary for a fair presentation of the accompanying unaudited condensed consolidated financial statements have been included, and all adjustments are of a normal and recurring nature.

Reclassification — During the first quarter of 2016, the Company revised the classification of certain health insurance premium and other employee fringe benefit expenses between the cost of revenues and selling, general and administrative expenses line items on the condensed consolidated statements of income and comprehensive income. The effect of this reclassification had no impact on total income from operations for the three and nine months ended September 30, 2016.

Revenue Recognition — The Company recognizes revenue when the following criteria are met: (1) persuasive evidence of an arrangement exists; (2) delivery has occurred; (3) the sales price is fixed or determinable; and (4) collectability is reasonably assured. Determining whether and when some of these criteria have been satisfied often involves assumptions and judgments that can have a significant impact on the timing and amount of revenue reported.

The Company derives its revenues from a variety of service offerings, which represent specific competencies of its IT professionals. Contracts for these services have different terms and conditions based on the scope, deliverables, and complexity of the engagement, which require management to make judgments and estimates in determining the appropriate revenue recognition. Fees for these contracts may be in the form of time-and-materials or fixed-price arrangements. If there is an uncertainty about the project completion or receipt of payment for the services, revenue is deferred until the uncertainty is sufficiently resolved. At the time revenue is recognized, the Company provides for any contractual deductions and reduces the revenue accordingly. The Company reports gross reimbursable “out-of-pocket” expenses incurred as both revenues and cost of revenues in the condensed consolidated statements of income and comprehensive income.

The Company defers amounts billed to its clients for revenues not yet earned. Such amounts are anticipated to be recorded as revenues when services are performed in subsequent periods. Unbilled revenue is recorded when services have been provided but billed subsequent to the period end in accordance with the contract terms.

Fair Value of Financial Instruments — The Company makes assumptions about fair values of its financial assets and liabilities in accordance with the Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 820, “Fair Value Measurement”, and utilizes the following fair value hierarchy in determining inputs used for valuation:

Level 1 — Quoted prices for identical assets or liabilities in active markets.

Level 2 — Inputs other than quoted prices within Level 1 that are observable either directly or indirectly, including quoted prices in markets that are not active, quoted prices in active markets for similar assets or liabilities, and observable inputs other than quoted prices such as interest rates or yield curves.

Level 3 — Unobservable inputs reflecting our view about the assumptions that market participants would use in pricing the asset or liability.

Where the fair values of financial assets and liabilities recorded in the condensed consolidated balance sheets cannot be derived from an active market, they are determined using a variety of valuation techniques. These valuation techniques include a net present value technique, comparison to similar instruments with market observable inputs, option pricing models and other relevant valuation models. To the extent possible, observable market data is used as inputs into these models but when it is not feasible, a degree of judgment is required to establish fair values.

The Company’s contingent liabilities measured at fair value on a recurring basis are comprised of performance-based awards issued to certain former owners of acquired businesses in exchange for future services and cash settled restricted stock units issued to employees.

Performance-based awards issued to certain former owners of acquired businesses are valued using significant inputs that are not observable in the market, which are defined as Level 3 inputs according to fair value measurement accounting. The Company believes its estimates and assumptions are reasonable, however, there is significant judgment involved.

Cash settled restricted stock units issued to employees are valued using the price of the Company's stock, a significant input that is observable in the market, which is defined as Level 1 input according to fair value measurement accounting.

These changes in fair value could cause a material impact to, and volatility in the Company’s operating results. See Note 4 for disclosures related to fair value.

Employee Loans — The Company issues employee housing loans in Belarus, relocation loans to assist employees with relocation needs in connection with intra-company transfers and loans for the purchase of automobiles in India. There are no loans issued to principal officers, directors, and their affiliates. The Company intends to hold all employee loans until their maturity. Interest income is reported using the effective interest method. Where applicable, loan origination fees, net of direct origination costs, are deferred and recognized in interest income over the life of the loan.

On a quarterly basis, the Company reviews the aging of its loan portfolio and evaluates the ability of employees to repay their debt on schedule. Factors considered in the review include historical payment experience, reasons for payment delays and shortfalls, if any, as well as probability of collecting scheduled principal and interest payments. Since the initiation of the loan program there have not been material past due or non-accrual employee loans or write offs related to loan losses and, therefore, the Company determined that no allowance for loan losses is required.

Employee Housing Loans — In 2012, the Board of Directors of the Company approved the Employee Housing Program (the “Housing Program”), which provides employees with loans to purchase housing in Belarus. The housing is sold directly to employees by independent third parties. The Housing Program was designed as a retention mechanism for the Company’s employees in Belarus and is available to full-time qualified employees who have been with the Company for at least three years. The aggregate maximum lending limit of the program is $10,000, with individual loans not exceeding $50. Loans issued under the Housing Program are denominated in U.S. dollars with a 5-year term and an interest rate of 7.5%.

The housing loans are measured using the Level 3 inputs within the fair value hierarchy because they are valued using significant unobservable inputs. These housing loans are measured at fair value upon initial recognition through the market approach under ASC Topic 820, “Fair Value Measurement” and subsequently carried at amortized cost less allowance for loan losses, if any. Any difference between the carrying value and the fair value of a loan upon initial recognition is charged to expense.

Employee Loans, Other — The Company issues short-term, non-interest bearing relocation loans to employees who have relocated within the company. In addition, the Company has in the past issued and may issue in the future a small number of interest bearing loans to employees for the purchase of automobiles. Such loans are issued to qualified employees with certain conditions attached. Due to the short term duration of these employee loans and high certainty of repayment, their carrying amount is a reasonable estimate of their fair value.

Business Combinations — The Company accounts for its business combinations using the acquisition accounting method, which requires it to determine the fair value of net assets acquired and the related goodwill and other intangible assets in accordance with the FASB ASC Topic 805, “Business Combinations.” The Company identifies and attributes fair values and estimated lives to the intangible assets acquired and allocates the total cost of an acquisition to the underlying net assets based on their respective estimated fair values. Determining the fair value of assets acquired and liabilities assumed requires management’s judgment and involves the use of significant estimates, including projections of future cash inflows and outflows, discount rates, asset lives and market multiples. There are different valuation models for each component, the selection of which requires considerable judgment. These determinations will affect the amount of amortization expense recognized in future periods. The Company bases its fair value estimates on assumptions it believes are reasonable, but recognizes that the assumptions are inherently uncertain.

If initial accounting for the business combination has not been completed by the end of the reporting period in which the business combination occurs, provisional amounts are reported for which the accounting is incomplete, with retrospective adjustment made to such provisional amounts during the measurement period to present new information about facts and circumstances that existed as of the acquisition date.

All acquisition-related costs, other than the costs to issue debt or equity securities, are accounted for as expenses in the period in which they are incurred. Changes in fair value of contingent consideration arrangements that are not measurement period adjustments are recognized in earnings. Payments to settle contingent consideration, if any, are reflected in cash flows from financing activities and the changes in fair value are reflected in cash flows from operating activities in the Company’s condensed consolidated statements of cash flows.

The acquired assets typically consist of customer relationships, trade names, non-competition agreements, and workforce and as a result, a substantial portion of the purchase price is usually allocated to goodwill and other intangible assets.

Goodwill and Other Intangible Assets — Goodwill and intangible assets that have indefinite useful lives are accounted for in accordance with FASB ASC 350, “Intangibles - Goodwill and Other.” The Company conducts its evaluation of goodwill impairment at the reporting unit level on an annual basis during its fourth quarter, and more frequently if events or circumstances indicate that the carrying value of a reporting unit exceeds its fair value. A reporting unit is an operating segment or one level below. The Company does not have intangible assets that have indefinite useful lives.

Intangible assets that have finite useful lives are amortized over their estimated useful lives on a straight-line basis. When facts and circumstances indicate potential impairment of amortizable intangible assets, the Company evaluates the recoverability of the asset’s carrying value, using estimates of future cash flows over the remaining asset life. The estimates of future cash flows attributable to intangible assets require significant judgment based on the Company’s historical and anticipated results. Any impairment loss is measured by the excess of carrying value over fair value.

Stock-Based Compensation — The Company recognizes the cost of its stock-based incentive awards based on the fair value of the award at the date of grant net of estimated forfeitures. The cost is expensed evenly over the service period. The service period is the period over which the employee performs the related services, which is normally the same as the vesting period. Over time, the forfeiture assumption is adjusted to the actual forfeiture rate and such change may affect the timing of the total amount of expense recognized over the vesting period. Equity-based awards that do not require future service are expensed immediately. Equity-based awards that do not meet the criteria for equity classification are recorded as liabilities and adjusted to fair value at the end of each reporting period.

Off-Balance Sheet Financial Instruments — The Company uses FASB ASC Topic 825, “Financial Instruments” to identify and disclose off-balance sheet financial instruments, which include credit instruments, such as commitments to make employee loans and related guarantees, standby letters of credit and certain guarantees issued under customer contracts. The face amount for these items represents the exposure to loss, before considering available collateral or the borrower’s ability to repay. Loss contingencies arising from off-balance sheet financial instruments are recorded as liabilities when the likelihood of loss is probable and an amount or range of loss can be reasonably estimated. The Company does not believe such matters exist that will have a material effect on the condensed consolidated financial statements.