Common Stock, Capital Shares Reserved For Future Issuance, Percent of Outstanding Shares to be Added Annually

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Number Of Additional Shares Authorized, Maximum Annual Amount

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Number Of Additional Shares Authorized, Percent Of Outstanding Shares

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

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

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

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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- Definition

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

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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.

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- Definition

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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- Definition

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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Stock-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Jan. 01, 2019	Jan. 01, 2018	Dec. 31, 2019	Dec. 31, 2018	Jan. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock eligible to be purchased (in shares)			7,483,000	6,515,000	1,753,758
Weighted average fair value of options granted (in dollars per share)			$ 2.76	$ 12.88
Intrinsic value of stock options exercised			$ 0.6	$ 5.7
Unrecognized stock-based compensation expense, options			$ 13.0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock eligible to be purchased (in shares)			0	7,000
Aggregate fair value of awards vested in period			$ 0.1	$ 0.1
Shares vested (in shares)			7,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock eligible to be purchased (in shares)			460,000	371,000
Aggregate fair value of awards vested in period			$ 0.7
Shares vested (in shares)			157,000	0
Unrecognized stock-based compensation expense			$ 1.7
Remaining weighted average vesting period			1 year 6 months 19 days
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining weighted average vesting period			2 years 3 months 22 days
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares)					0
Shares of common stock eligible to be purchased (in shares)					243,758
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares)			1,288,186
Shares of common stock eligible to be purchased (in shares)					1,510,000
Percent of outstanding shares able to be added each year					4.00%
Number of additional shares authorized (in shares)	1,317,935	1,290,609
2017 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock eligible to be purchased (in shares)					302,000
Number of additional shares authorized (in shares)	322,652	329,483
Percent of outstanding shares					1.00%
Maximum annual amount, shares authorized (in shares)					603,000