Income Taxes Unrecognized Tax Benefits (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Contingency [Line Items]
Unrecognized tax benefits	$ 28,615us-gaap_UnrecognizedTaxBenefits	$ 26,433us-gaap_UnrecognizedTaxBenefits	$ 28,482us-gaap_UnrecognizedTaxBenefits
Gross increase to positions in prior years	2,749	2,154	299
Gross decrease to positions in prior years	(1,641)	(536)	(51)
Gross increases to current period tax positions	3,008	1,670	3,347
Audit settlements	0	0	(27)
Decrease related to lapsing of statute of limitations	(1,715)	(817)	(5,769)
Effect of change in exchange rates	(2,870)	(289)	152
The amount of unrecognized tax benefits that, if recognized, would affect our effective tax rate	26,980	27,694	25,852
Net interest and penalties expense (benefit)	(76)	(898)	(414)
Accrued interest	1,755	2,078
Accrued penalties	2,671	3,075
Unrecognized tax benefits	$ 28,146us-gaap_UnrecognizedTaxBenefits	$ 28,615us-gaap_UnrecognizedTaxBenefits	$ 26,433us-gaap_UnrecognizedTaxBenefits

Effect of Change in Exchange Rates Unrecognized Tax Benefit

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

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-Publisher FASB

-Name Accounting Standards Codification

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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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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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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.

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

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Amount of interest expense accrued for an underpayment of income taxes.

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

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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