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Amount of cost to be recognized for option under share-based payment arrangement.

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

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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Equity Compensation Plans - Options (Details) - USD ($)		12 Months Ended
Equity Compensation Plans - Options (Details) - USD ($)	Dec. 31, 2009	Dec. 31, 2021	Dec. 31, 2019
2009 Plan
Equity Compensation Plans
Granted (in shares)	16,500	0
Exercised (in shares)		0	4,500
Shares
Exercised (in shares)		0	(4,500)
Ending outstanding (in shares)		0
Employee and Nonemployee Stock Options [Member]
Equity Compensation Plans
Total unrecognized compensation cost		$ 0
Aggregate Intrinsic Value
Exercised (in dollars)			$ (27,000)