(Schedule of Restricted Cash and Time Deposits) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Cash and Cash Equivalents [Line Items]
Time deposits	$ 0us-gaap_TimeDepositsAtCarryingValue	$ 1,188us-gaap_TimeDepositsAtCarryingValue
Short-term security deposits under customer contracts	0us-gaap_DepositsAssetsCurrent	298us-gaap_DepositsAssetsCurrent
Long-term deposits	156us-gaap_DepositsAssetsNoncurrent	225us-gaap_DepositsAssetsNoncurrent
Total	156epam_RestrictedCashAndTimeDeposits	1,711epam_RestrictedCashAndTimeDeposits
Time deposits
Cash and Cash Equivalents [Line Items]
Time deposits	0	1,188
Short-term security deposits under customer contracts
Cash and Cash Equivalents [Line Items]
Short-term security deposits under customer contracts	0	298
Long-term deposits under employee loan programs
Cash and Cash Equivalents [Line Items]
Long-term deposits	156	225
Long-term deposits under operating leases
Cash and Cash Equivalents [Line Items]
Long-term deposits	$ 0	$ 0

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage and any certificate of deposit or savings account held by a bank or other financial institution for a short-term specified period of time.

No definition available.

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- Definition

Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment within one year or during the operating cycle, if shorter.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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- Definition

Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer.

+ References

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- Definition

Any certificate of deposit or savings account held by a bank or other financial institution for a short-term specified period of time. Because of their short-term, time deposits are considered highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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