Taxation (Details - Income Tax Uncertainties) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Contingency [Line Items]
January 1	$ 20,568us-gaap_UnrecognizedTaxBenefits	$ 16,584us-gaap_UnrecognizedTaxBenefits	$ 12,290us-gaap_UnrecognizedTaxBenefits
Changes in tax positions taken during a prior period - Increase	1,597		2,075
Changes in tax positions taken during a prior period - decrease		(4,531)
Tax positions taken during the current period - increase	5,142	10,215	3,088
Change as a result of a lapse in the statute of limitations	(5,989)	(2,281)	(1,201)
Impact of the change in foreign currency exchange rates - decrease	(2,486)
Impact of the change in foreign currency exchange rates - increase		581	332
December 31	18,832us-gaap_UnrecognizedTaxBenefits	20,568us-gaap_UnrecognizedTaxBenefits	16,584us-gaap_UnrecognizedTaxBenefits
Unrecognized tax benefits that, if recognized, would impact the effective tax rate
Income Tax Contingency [Line Items]
January 1	19,353	15,784	11,879
Changes in tax positions taken during a prior period - Increase	1,338		1,571
Changes in tax positions taken during a prior period - decrease		(5,038)
Tax positions taken during the current period - increase	5,142	10,164	3,080
Change as a result of a lapse in the statute of limitations	(5,197)	(2,102)	(1,057)
Impact of the change in foreign currency exchange rates - decrease	(2,370)
Impact of the change in foreign currency exchange rates - increase		545	311
December 31	18,266	19,353	15,784
Interest and penalties recognized on the above
Income Tax Contingency [Line Items]
January 1	1,215	800	411
Changes in tax positions taken during a prior period - Increase	259	507	504
Tax positions taken during the current period - increase	0	51	8
Change as a result of a lapse in the statute of limitations	(792)	(179)	(144)
Impact of the change in foreign currency exchange rates - decrease	(116)
Impact of the change in foreign currency exchange rates - increase		36	21
December 31	$ 566	$ 1,215	$ 800

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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-Topic 740

-SubTopic 10

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-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in unrecognized tax benefits resulting from foreign currency translation.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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-Name Accounting Standards Codification

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