The maximum amount allowed for advance payroll deductions in a calendar year for employee stock purchase plan.

No definition available.

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- Definition

Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Annual Forfeiture Rate

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Grant Date Fair Value Of Awards

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement by Share based Payment Award, Vesting Percentage

+ References

No definition available.

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- Definition

Share Based Compensation Arrangements By Share Based Payment Award Percentage Of Market Price At Eligible Employees Granted Options To Purchase Shares

+ References

No definition available.

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- Definition

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

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- Definition

Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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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 option under share-based payment arrangement.

+ References

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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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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- 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.

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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

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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Share-Based Compensation - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of average closing price to be paid by employees		85.00%
Share-based compensation		$ 4,115,000	$ 3,592,000	$ 2,827,000
Estimated pre-vesting forfeiture rate (as a percent)		1.70%
Income tax benefit related to adoption of ASU 2016-09		$ 433,000	644,000	935,000
Aggregate intrinsic value of stock options exercised		495,000	1,685,000
Stock options exercised		144,000	$ 1,598,000	$ 2,398,000
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock purchases through advance payroll deductions in a calendar year		$ 25,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option term		10 years
Stock options vesting percentage		100.00%
Unrecognized compensation expense	$ 0	$ 0
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested period		1 year
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested period		2 years
RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested period		3 years
Unrecognized compensation expense	7,422,000	$ 7,422,000
Unrecognized compensation expense expected recognition period		1 year 7 months 6 days
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	0	$ 0
Grant date fair value of ESPP options	$ 29,000