Increase (decrease) in number of shares authorized.

No definition available.

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- Definition

Sale of Stock, Purchase Option Term

+ References

No definition available.

+ Details

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- Definition

Share-Based Compensation, Evergreen Option Provision, Equity Increase

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Participation Term

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Purchase Interval

+ References

No definition available.

+ Details

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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- Definition

Discount rate from fair value on offering date that participants pay for shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

+ 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 highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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.

+ References

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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- Definition

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

+ References

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- Definition

Number of share options (or share units) exercised during the current period.

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Equity Transactions and Share-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended		6 Months Ended
	Jan. 20, 2021	Jan. 01, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Common stock, par value (in dollars per share)	$ 0.001		$ 0.001		$ 0.001		$ 0.001
Shares issued for restricted stock units (in shares)			0	0	169,000	163,000
Public Stock Offering
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares sold (in shares)	11,765,000
Price of shares sold (in dollars per share)	$ 8.50
Proceeds from shares sold	$ 107.8
Underwriter's Option
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares sold (in shares)	1,764,750
Price of shares sold (in dollars per share)	$ 7.99
Purchase option term	30 days
The 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Evergreen option provision, equity increase					4.00%
Additional shares authorized (in shares)		2,500,000
Number of shares reserved for future issuance (in shares)			2,200,000		2,200,000
Shares issued pursuant to the exercise of stock options (in shares)			41,000	242,000	752,000	242,000
The 2013 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award
Evergreen option provision, equity increase					1.00%
Additional shares authorized (in shares)		422,535
Number of shares reserved for future issuance (in shares)			2,600,000		2,600,000
Number of shares authorized to be granted (in shares)			3,900,000		3,900,000
Number of shares reserved for issuance, annual increase (in shares)					422,535
Participation term					24 months
Percentage of pay that employee can contribute, maximum			15.00%		15.00%
Discounted purchase price from market price, offering date					15.00%
Discounted purchase price from market price, purchase date					15.00%
Purchase interval					6 months
Shares issued pursuant to employee stock purchase plan (in shares)					260,000	177,000