Number of Customers

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

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OPERATING SEGMENTS (Revenues from External Customers and Segment Operating Profit Before Unallocated Expenses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenues	$ 202,184us-gaap_SalesRevenueNet	$ 192,764us-gaap_SalesRevenueNet	$ 174,695us-gaap_SalesRevenueNet	$ 160,384us-gaap_SalesRevenueNet	$ 157,585us-gaap_SalesRevenueNet	$ 140,150us-gaap_SalesRevenueNet	$ 133,184us-gaap_SalesRevenueNet	$ 124,198us-gaap_SalesRevenueNet	$ 730,027us-gaap_SalesRevenueNet	$ 555,117us-gaap_SalesRevenueNet	$ 433,799us-gaap_SalesRevenueNet
Operating profit	24,015us-gaap_OperatingIncomeLoss	21,835us-gaap_OperatingIncomeLoss	18,476us-gaap_OperatingIncomeLoss	21,857us-gaap_OperatingIncomeLoss	23,192us-gaap_OperatingIncomeLoss	20,230us-gaap_OperatingIncomeLoss	17,535us-gaap_OperatingIncomeLoss	15,536us-gaap_OperatingIncomeLoss	86,183us-gaap_OperatingIncomeLoss	76,493us-gaap_OperatingIncomeLoss	66,006us-gaap_OperatingIncomeLoss
Entity-wide revenue, major customer, amount									730,027us-gaap_Revenues	555,117us-gaap_Revenues	433,799us-gaap_Revenues
Russia
Segment Reporting Information [Line Items]
Revenues									48,945	53,328	47,507
Operating Segments
Segment Reporting Information [Line Items]
Revenues									730,003	555,043	433,722
Operating profit									144,619	109,308	87,455
Entity-wide revenue, major customer, amount									730,003	555,043	433,722
Operating Segments \| North America
Segment Reporting Information [Line Items]
Revenues									374,509	284,636	197,271
Operating profit									90,616	66,814	38,671
Operating Segments \| Europe
Segment Reporting Information [Line Items]
Revenues									299,279	204,150	168,913
Operating profit									50,189	34,573	32,750
Operating Segments \| Russia
Segment Reporting Information [Line Items]
Revenues									50,663	55,764	50,552
Operating profit									7,034	7,077	9,049
Operating Segments \| Other
Segment Reporting Information [Line Items]
Revenues									5,552	10,493	16,986
Operating profit									(3,220)	844	6,985
Sales Revenue, Net \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Number of customers										0
Sales Revenue, Net \| Customer Concentration Risk \| UBS AG
Segment Reporting Information [Line Items]
Entity-wide revenue, major customer, amount									97,600
Number of customers									1
Sales Revenue, Net \| Customer Concentration Risk \| Europe \| UBS AG
Segment Reporting Information [Line Items]
Entity-wide revenue, major customer, amount									$ 97,872
Unbilled Revenues \| Customer Concentration Risk \| UBS AG
Segment Reporting Information [Line Items]
Percentage of total revenues									16.50%
Number of customers									1
Accounts Receivable Billed \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Number of customers									0