Financial Instruments - Carrying Value and Estimated Fair Value of Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value Disclosures [Abstract]
Cash and cash equivalents, Carrying amount	$ 45,570	$ 38,753	$ 63,777	$ 10,081
Accounts receivable, net, Carrying amount	8,747us-gaap_AccountsReceivableNetCurrent	8,534us-gaap_AccountsReceivableNetCurrent
Accounts payable, Carrying amount	3,850us-gaap_AccountsPayableCurrent	1,452us-gaap_AccountsPayableCurrent
Cash and cash equivalents, Fair value	45,570	38,753
Accounts receivable, net, Fair value	8,747	8,534
Accounts payable, Fair value	$ 3,850	$ 1,452

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. 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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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-Publisher FASB

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- Definition

Fair value portion of liabilities incurred for goods and services received that are used in an entity's business and related party payables.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13487-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Fair value portion of amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13487-108611

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher SEC

-Name Regulation S-X (SX)

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-Paragraph 3

-Subparagraph a(1)

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-Name Regulation S-X (SX)

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.1)

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-Topic 230

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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