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

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- Definition

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

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- Definition

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

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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

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- Definition

Amount of decrease in additional paid in capital (APIC) resulting from a tax deficiency associated with a share-based compensation plan other than an employee stock ownership plan (ESOP).

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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- Definition

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

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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.

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- Definition

Amount of cash inflow from exercise of 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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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

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, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
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		$ 4,600,000	$ 4,115,000	$ 3,592,000
Estimated pre-vesting forfeiture rate (as a percent)		0.40%
Aggregate intrinsic value of stock options exercised		$ 261,000	495,000
Stock options exercised		$ 115,000	144,000	1,598,000
RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested period		3 years
Income tax expense at vesting		$ 394,000
Income tax benefit at vesting			$ 363,000	$ 448,000
Unrecognized compensation expense	$ 6,721,000	$ 6,721,000
Unrecognized compensation expense expected recognition period		1 year 8 months 23 days
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
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	0	$ 0
Grant date fair value of ESPP options	$ 19,000
Minimum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested period		1 year
Maximum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested period		2 years