Business combination contingent consideration arrangements of shares issued.

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Common stock trading period.

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- Definition

Section 382 Rights Agreement, Acquiring Person, Trigger, Percentage of Common Shares Outstanding

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- Definition

Share Based Compensation, Employee Stock Purchase Plans, Share Outstanding

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- Definition

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

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Aggregate number of common shares reserved for future issuance.

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- Definition

The per share price that the individual must pay to acquire shares under the deferred compensation arrangement.

+ References

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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- Definition

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

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- Definition

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

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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- Definition

The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

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- Definition

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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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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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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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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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Stockholders' Equity - Additional Information (Details)		3 Months Ended		6 Months Ended	9 Months Ended
Stockholders' Equity - Additional Information (Details)	Nov. 06, 2018 $ / shares shares	Jun. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2018 USD ($)	Mar. 31, 2017 shares	Jun. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2018 USD ($)	Sep. 30, 2015 shares	Feb. 28, 2019	Oct. 23, 2018 $ / right $ / shares shares	Sep. 30, 2018 USD ($) $ / shares shares	Mar. 07, 2018 shares	Mar. 10, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $		$ 18,800,000			$ 18,800,000
Weighted average period for unrecognized compensation expense expected to be recognized (in years)					2 years 6 months
Purchase of common stock (in shares)		1,664,565			1,664,565					2,806,364
Discount rate from market price, purchase date					0.15
Recognized compensation expense \| $		$ 2,268,000	$ 1,980,000		$ 7,291,000	$ 5,927,000
Total intrinsic value of options exercised \| $					$ 11,000,000.0	1,200,000
Weighted average fair value of options granted (in dollars per share) \| $ / shares					$ 5.08
Aggregate intrinsic value of options outstanding \| $		$ 5,400,000			$ 5,400,000					$ 12,800,000
Preferred stock, par value (in dollars per share) \| $ / shares		$ 0.001			$ 0.001				$ 0.001	$ 0.001
Percentage of common stock outstanding for acquiring person under right agreement								4.90%
Earnout shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized compensation expense \| $					$ 0	400,000
Earnout shares \| IDchecker
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Business combination, paid earnout shares issued (in shares)				81,182			137,306
Common stock trading period (in days)					10 days
Series B Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of preferred share purchase right for each share of common stock (in shares)									1
Preferred stock, share conversion ratio									0.001
Preferred stock, purchase price per right (in dollars per right) \| $ / right									35.00
Preferred stock, redemption price per share (in dollars per share) \| $ / shares									$ 0.0001
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for unrecognized compensation expense expected to be recognized (in years)					2 years 6 months
RSUs outstanding (in shares)		2,497,671			2,497,671					2,580,176
Recognized compensation expense \| $		$ 1,600,000	1,300,000		$ 5,300,000	3,900,000
Unrecognized compensation expense related to nonvested awards \| $		14,100,000			$ 14,100,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for unrecognized compensation expense expected to be recognized (in years)					3 years 1 month 6 days
Recognized compensation expense \| $		200,000	300,000		$ 500,000	900,000
Unrecognized compensation expense related to outstanding stock options \| $		1,900,000			1,900,000
Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $		800,000			$ 800,000
Weighted average period for unrecognized compensation expense expected to be recognized (in years)					1 year 2 months 12 days
Performance Options \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $		1,900,000			$ 1,900,000
Weighted average period for unrecognized compensation expense expected to be recognized (in years)					2 years 4 months 24 days
Number of common stock reserved for future grants (in shares)	800,000
Recognized compensation expense \| $		$ 200,000			$ 500,000
Exercise price per share (in dollars per share) \| $ / shares	$ 9.50
Vesting period of awards	3 years
2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)												9,500,000
Purchase of common stock (in shares)		1,194,371			1,194,371
Number of common stock reserved for future grants (in shares)		757,135			757,135
2012 Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs outstanding (in shares)		2,036,063			2,036,063
2012 Plan \| Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs outstanding (in shares)		1,703,569			1,703,569
Recognized compensation expense \| $		$ 200,000	$ 400,000		$ 700,000	$ 1,100,000
Prior Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of common stock (in shares)		298,015			298,015
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)		871,658			871,658						1,000,000
Shares outstanding under ESPP (in shares)		128,342			128,342
Recognized compensation expense \| $		$ 100,000			$ 300,000
Director Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)												1,500,000
Number of common stock reserved for future grants (in shares)		391,701			391,701
Director Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of common stock (in shares)		366,870			366,870
Minimum \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount rate from market price, offering date					15.00%