No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

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

+ 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
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

No definition available.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Stock-Based Compensation - Stock Option Transactions Under Various Stock-Based Employee Compensation Plans (Detail) - $ / shares	3 Months Ended				12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding, Beginning Balance, Shares		608,375		836,859	836,859
Granted, Shares					117,000
Exercised, Shares	(13,642)	(14,609)	(85,379)	(186,521)	(340,684)	(361,618)	(554,049)
Forfeited, Shares					(4,800)
Outstanding, Ending Balance, Shares					608,375	836,859
Exercisable, Ending Balance, Shares					401,375
Outstanding, Beginning Balance, Weighted Average Exercise Price		$ 57.97		$ 49.65	$ 49.65
Granted, Weighted Average Exercise Price					76.92
Exercised, Weighted-Average Exercise Price					43.98
Forfeited, Weighted Average Exercise Price					61.23
Outstanding, Ending Balance, Weighted Average Exercise Price					57.97	$ 49.65
Exercisable, Ending Balance, Weighted Average Exercise Price					$ 50.64
Outstanding, Ending balance, Weighted Average Remaining Contractual Term					5 years 8 months 15 days
Exercisable, Ending Balance, Weighted Average Remaining Contractual Term					4 years 3 months 21 days