Summary of Changes in Restructuring-Related Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 2,284us-gaap_RestructuringReserveCurrent
Costs Incurred	85us-gaap_RestructuringCharges	0us-gaap_RestructuringCharges
Adjustments and Other	98	0
Ending Balance	879us-gaap_RestructuringReserveCurrent
Accrued restructuring costs \| Current accrued restructuring costs
Restructuring Cost and Reserve [Line Items]
Beginning Balance	2,284
Costs Incurred	85
Cash Payments	(1,218)
Non-cash Settlements	0
Adjustments and Other	(272)
Ending Balance	879
Accrued restructuring costs \| Current accrued restructuring costs \| Severance and related employee benefits
Restructuring Cost and Reserve [Line Items]
Beginning Balance	2,215
Costs Incurred	0
Cash Payments	(1,089)
Non-cash Settlements	0
Adjustments and Other	(286)
Ending Balance	840
Accrued restructuring costs \| Current accrued restructuring costs \| Contract termination costs
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Costs Incurred	0
Cash Payments	0
Non-cash Settlements	0
Adjustments and Other	0
Ending Balance	0
Accrued restructuring costs \| Current accrued restructuring costs \| Other costs
Restructuring Cost and Reserve [Line Items]
Beginning Balance	69
Costs Incurred	85
Cash Payments	(129)
Non-cash Settlements	0
Adjustments and Other	14
Ending Balance	$ 39

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount of any reversal and other adjustment made during the period to the amount of a previously accrued liability for a specified type of restructuring cost, excluding adjustments for costs incurred during the period, costs settled during the period, and foreign currency translation adjustments.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Amount of consideration other than cash used to fully or partially settle an accrued restructuring cost.

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