Commitments and Contingencies - Summary of Liability Related to Lease (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Commitments and Contingencies Disclosure [Abstract]
Beginning balance	$ 1,787	$ 1,103
Net rental receipts (payments)	(281)	(410)
Accretion of discount	125	61
Increase in net estimated contract termination costs	1,018	1,144
Ending balance	$ 2,649	$ 1,898

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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 45

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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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-SubTopic 10

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-Subparagraph (b)

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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