Component of common stock capital shares reserved for future issuance.

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Increase (decrease) in share based payment award number of shares available for grant.

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Maximum amount of annual employee common stock purchases.

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Percentage of common share outstanding, as it relates to the number of shares reserved for future issuance calculation under the 2014 Stock Incentive Plan.

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Share based compensation arrangement by share based payment award number of shares available for grant description.

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Share based compensation arrangement by share based payment award options grants in period gross value grant date fair value.

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Share based compensation arrangement by share based payment award other than options grants in period gross value grant date fair value.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Number of shares purchased for issuance under share-based payment arrangement.

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Purchase price of common stock expressed as a percentage of its fair value.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)		12 Months Ended
	Jan. 08, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2018
Share-Based Compensation
Fair value of vested stock options		$ 3,100,000	$ 3,000,000	$ 3,500,000
Stock-based compensation expense		$ 5,437,000	9,768,000	4,705,000
T2-Owned Instruments and Components [Member]
Share-Based Compensation
Stock-based compensation expense			100,000	100,000
Employee Stock Purchase Plan [Member]
Share-Based Compensation
Shares available for grant		142,432
Shares available for authorization		220,588
Percentage of full share price paid in purchase of common stock		85.00%
Maximum amount of annual employee common stock purchases		$ 25,000
Stock-based compensation expense		$ 400,000	400,000	200,000
Number of shares purchased by participants		306,824
Number of shares available for grant description		In addition, on the first day of each calendar year beginning January 1, 2015 and ending on January 1, 2024, the number of common shares available under the 2014 ESPP shall be increased by the number of shares equal to the lesser of (1) 220,588 shares, (2) 1% of the common shares outstanding on the final day of the immediately preceding calendar year and (3) such smaller number of common shares as determined by the Board of Directors.
Percentage of common shares outstanding		1.00%
Subsequent Event [Member]
Share-Based Compensation
Increase in shares available for grant	4,000,000
Restricted Stock Units [Member]
Share-Based Compensation
Weighted-average period		2 years
Unrecognized compensation cost related to unvested stock options		$ 1,300,000
2014 Stock Option Plan [Member] \| Stock Options [Member]
Share-Based Compensation
Shares available for future issuance under stock incentive plan		823,529
Percentage of common shares outstanding		4.00%
Shares available for grant		537,754
2014 Stock Option Plan [Member] \| Restricted Stock Units [Member]
Share-Based Compensation
Restricted stock units vested		189,129
Restricted stock units granted		589,142
Inducement Award Plan [Member]
Share-Based Compensation
Shares available for grant		717,000
Shares available for authorization					1,625,000
Inducement Award Plan [Member] \| Subsequent Event [Member]
Share-Based Compensation
Shares available for grant	5,625,000
2006 and 2014 Stock Option Plans [Member] \| Stock Options [Member]
Share-Based Compensation
Aggregate fair value of options granted		$ 3,900,000	5,800,000	2,700,000
Unrecognized compensation cost related to non-vested stock options		$ 5,800,000
Weighted-average period		2 years 7 months 6 days
2006 and 2014 Stock Option Plans and Inducement Plan [Member] \| Stock Options [Member]
Share-Based Compensation
Total intrinsic value of options exercised		$ 1,000	$ 1,400,000	$ 600,000
Weighted average fair value of options granted		$ 1.41	$ 3.54	$ 2.95
2006 and 2014 Stock Option Plans and Inducement Plan [Member] \| Restricted Stock Units [Member]
Share-Based Compensation
Aggregate fair value of restricted stock units granted		$ 1,900,000
2006 and 2014 Stock Option Plans and Inducement Plan [Member] \| Restricted Stock Units [Member] \| Restricted Stock Units Vested, Reflected As Outstanding Shares [Member]
Share-Based Compensation
Restricted stock units vested			78,172
2006 and 2014 Stock Option Plans and Inducement Plan [Member] \| Restricted Stock Units [Member] \| Restricted Stock Units Vested, Not Reflected As Outstanding Shares [Member]
Share-Based Compensation
Restricted stock units vested			73,172
2006 and 2014 Stock Option Plans and Inducement Plan [Member] \| Restricted Stock Units with Market Condition [Member]
Share-Based Compensation
Restricted stock units granted		755,168
Compensation Cost		$ 1,000,000	$ 4,500,000
Maximum [Member] \| 2006 Stock Option Plan [Member] \| Stock Options [Member]
Share-Based Compensation
Expiration period		10 years
Vesting period		4 years
Maximum [Member] \| 2014 Stock Option Plan [Member] \| Stock Options [Member]
Share-Based Compensation
Expiration period		10 years
Vesting period		4 years