Other Income (Expense), Net - Schedule of Other Income (Expense), Net (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Income:
Interest income	$ 163us-gaap_InterestIncomeOther	$ 386us-gaap_InterestIncomeOther	$ 460us-gaap_InterestIncomeOther
Foreign currency forward contract gains, net	0	12	0
Foreign currency exchange gains, net	8	0	0
Total other income	171us-gaap_OtherNonoperatingIncome	398us-gaap_OtherNonoperatingIncome	460us-gaap_OtherNonoperatingIncome
Other Expense:
Skyfence holdback liability accretion	(186)us-gaap_AccretionExpense	0us-gaap_AccretionExpense	0us-gaap_AccretionExpense
Foreign currency forward contract losses, net	0	0	(19)
Foreign currency exchange losses, net	0	(373)	(497)
Other	(205)us-gaap_OtherExpenses	(150)us-gaap_OtherExpenses	(187)us-gaap_OtherExpenses
Total other expense	(391)us-gaap_OtherNonoperatingExpense	(523)us-gaap_OtherNonoperatingExpense	(703)us-gaap_OtherNonoperatingExpense
Total other income (expense), net	$ (220)us-gaap_OtherNonoperatingIncomeExpense	$ (125)us-gaap_OtherNonoperatingIncomeExpense	$ (243)us-gaap_OtherNonoperatingIncomeExpense

Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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

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

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Aggregate gain on all derivative instruments recognized in earnings during the period, before tax effects.

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Amount of interest income earned from interest bearing assets not separately disclosed.

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This element represents a sum total of expenses not separately reflected on the income statement for the period.

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The aggregate amount of other 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 expense recognized during the period. Such amounts may include: (a) unusual costs, (b) loss on foreign exchange transactions, (c) losses on securities (net of profits), and (d) miscellaneous other expense items.

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The aggregate amount of other income 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 recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) profits on securities (net of losses), and (d) miscellaneous other income items.

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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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