Available for sale securities continuous unrealized loss position for more than three months accumulated loss.

No definition available.

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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- Definition

Amount, before tax, of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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- Details

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- Details

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- Details

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Period Type:

- Details

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Investments and Fair Value of Financial Instruments - Additional Information (Detail) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Jun. 14, 2018	Mar. 22, 2018
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investment in continuous unrealized loss position for more than three months	$ 0
Unrealized gains and losses included in accumulated other comprehensive income or loss	0	$ 0
Other-than-temporary impairments associated with credit losses required to be recognized	$ 0
Common Stock Warrant Liability [Member] \| Securities Purchase Agreement [Member] \| Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Shares of common stock issued				1,282,832
Common Stock Warrant Liability [Member] \| Securities Purchase Agreement [Member] \| Level 3 [Member] \| June 2018 Offering [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Shares of common stock issued			1,461,962