Other Non-Operating Income (Expense), Net (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other non-operating income [Abstract]
Interest and dividend income	$ 296us-gaap_OtherInterestAndDividendIncome	$ 302us-gaap_OtherInterestAndDividendIncome	$ 167us-gaap_OtherInterestAndDividendIncome
Equity income (loss) from joint ventures	(822)	(285)	0
Gain (loss) on foreign exchange	(1,562)	(143)	(380)
Other income (expense), net	119us-gaap_OtherNonoperatingIncomeExpense	127us-gaap_OtherNonoperatingIncomeExpense	(483)us-gaap_OtherNonoperatingIncomeExpense
Total other non-operating income (expense), net	$ (1,969)us-gaap_NonoperatingIncomeExpense	$ 1us-gaap_NonoperatingIncomeExpense	$ (696)us-gaap_NonoperatingIncomeExpense

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Includes all other interest income, net of discount accretion and premium amortization, and dividend income. It may include dividend income from equity securities that do not have readily determinable fair values that are reportable in Other Assets, and interest income on interest-only strips receivable (not in the form of a security) that are included in Other Assets.

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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