Commitments and Contingencies [Line Items]

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- Definition

Lease Agreement Area

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No definition available.

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- Definition

Lease Agreement Term

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No definition available.

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- Definition

Lease Agreement Termination Description

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- Definition

Lease Commencement Date

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No definition available.

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- Definition

Number Of Buildings Leased

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No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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No definition available.

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- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

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No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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- Definition

The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

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Commitments and Contingencies - Additional Information (Detail) $ in Thousands	1 Months Ended		3 Months Ended								12 Months Ended
	Mar. 31, 2014 USD ($) ft²	Jul. 31, 2011 USD ($) ft²	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) ft² Building	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2008 ft²	Mar. 31, 2007 ft²	Mar. 31, 2001 ft²
Commitments and Contingencies [Line Items]
Lease agreement, term	8 years 1 month	11 years												2 years	5 years	10 years
Lease agreement, space \| ft²		55,694									45,000			7,350	2,500	25,000
Lease agreement, expiration date		May 31, 2023									Dec. 31, 2021
Lease agreement, letter of credit issued		$ 200
Lease agreement, commencement date	Aug. 01, 2014
Future minimum rental commitment, 2018			$ 3,611								$ 3,611
Future minimum rental commitment, 2019			3,383								3,383
Future minimum rental commitment, 2020			3,077								3,077
Future minimum rental commitment, 2021			2,750								2,750
Future minimum rental commitment, 2022			1,464								$ 1,464
Lease termination description											The Company terminated the lease on the 7,350 square feet of space in the first quarter of 2015.
Lease agreement, number buildings leased \| Building											4
Operating leases, rent expense											$ 3,367	$ 2,644	$ 2,619
Operating leases, deferred rent liabilities			1,656				$ 1,792				1,656	1,792	1,899
Research and development expenses			3,069	$ 2,001	$ 1,860	$ 1,742	$ 2,040	$ 1,886	$ 1,890	$ 1,539	8,672	7,355	5,740
Purchase orders, supply agreements and other contractual obligations			15,512								15,512
Licensing Agreements
Commitments and Contingencies [Line Items]
Research and development expenses											161	$ 5	$ 7
Before Amendment
Commitments and Contingencies [Line Items]
Lease agreement, space \| ft²	55,694
Security deposit	$ 200
After Amendment
Commitments and Contingencies [Line Items]
Lease agreement, space \| ft²	75,594
Security deposit	$ 450
Future minimum rental commitment, 2018			1,371								1,371
Future minimum rental commitment, 2019			1,371								1,371
Future minimum rental commitment, 2020			1,371								1,371
Future minimum rental commitment, 2021			1,371								1,371
Future minimum rental commitment, 2022			1,251								1,251
Expansion Space
Commitments and Contingencies [Line Items]
Lease agreement, space \| ft²	19,900
Annual rent expense	$ 361
Renewal Term
Commitments and Contingencies [Line Items]
Future minimum rental commitment, 2018			1,087								1,087
Future minimum rental commitment, 2019			1,087								1,087
Future minimum rental commitment, 2020			1,087								1,087
Future minimum rental commitment, 2021			$ 1,087								$ 1,087