v3.21.2

STOCKHOLDERS' EQUITY - Stock Options (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Options, granted (in shares)			0	0
Options
Forfeited or expired (in shares)			(1,742)
Weighted-Average Exercise Price
Forfeited or expired, Weighted-Average Exercise Price (in dollars per share)			$ 30.97
Stock option
Share-based Compensation Arrangement by Share-based Payment Award
Options, granted (in shares)	0	0
Options
Outstanding at period start (in shares)			12,802
Exercised (in shares)			(4,422)
Outstanding at period end (in shares)	6,638		6,638		12,802
Weighted-Average Exercise Price
Outstanding at period start, weighted-average exercise price (in dollars per share)			$ 30.97
Exercised, weighted-average exercise price (in dollars per share)			30.97
Outstanding at period end, weighted-average exercise price (in dollars per share)	$ 30.97		$ 30.97		$ 30.97
Contractual terms (in years)			1 year 7 months 6 days		1 year 7 months 6 days
Vesting period (in years)			3 years
Stock-based compensation expense	$ 0	$ 0	$ 0	$ 0

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- Definition

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

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For presentations that combine terminations, 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 or that expired.

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

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

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

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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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