Commitments and Contingencies - Schedule of Future Lease Cash Payments under the Build to Suit Lease (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Build-To-Suit Lease, 2015	$ 2,435
Build-To-Suit Lease, 2016	2,538
Build-To-Suit Lease, 2017	2,614
Build-To-Suit Lease, 2018	2,692
Build-To-Suit Lease, 2019	2,773
Build-To-Suit Lease, 2019 and thereafter	14,162
Total minimum lease payments	$ 27,214

Amount of future minimum payments under build-to-suit lease.

No definition available.

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Amount of future minimum payments maturing in the next fiscal year following the latest fiscal year ended under build-to-suit lease.

No definition available.

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Amount of future minimum payments maturing in the fifth fiscal year following the latest fiscal year ended under build-to-suit lease.

No definition available.

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Amount of future minimum payments maturing in the fourth fiscal year following the latest fiscal year ended under build-to-suit lease.

No definition available.

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Amount of future minimum payments maturing in the third fiscal year following the latest fiscal year ended under build-to-suit lease.

No definition available.

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Amount of future minimum payments maturing in the second fiscal year following the latest fiscal year ended under build-to-suit lease.

No definition available.

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Amount of future minimum payments maturing after the fifth fiscal year following the latest fiscal year ended under build-to-suit lease.

No definition available.

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