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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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.

+ 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
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Stock Compensation Plans, Summary of Information about Stock Options Outstanding (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Number of options outstanding (in shares)	8,109,726
Number of options exercisable (in shares)	6,297,849	7,786,934	8,449,389
December 20, 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 14.50
Number of options outstanding (in shares)	874,014
Weighted-average remaining contractual life	1 year
Number of options exercisable (in shares)	874,014
December 19, 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 15.90
Number of options outstanding (in shares)	1,784,970
Weighted-average remaining contractual life	2 years
Number of options exercisable (in shares)	1,784,970
December 18, 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 15.80
Number of options outstanding (in shares)	1,116,965
Weighted-average remaining contractual life	3 years
Number of options exercisable (in shares)	1,116,965
December 21, 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 17.60
Number of options outstanding (in shares)	735,700
Weighted-average remaining contractual life	1 year
Number of options exercisable (in shares)	735,700
December 20, 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 13.69
Number of options outstanding (in shares)	824,877
Weighted-average remaining contractual life	2 years
Number of options exercisable (in shares)	824,877
March 4, 2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 13.51
Number of options outstanding (in shares)	10,000
Weighted-average remaining contractual life	2 years 2 months 12 days
Number of options exercisable (in shares)	10,000
December 19, 2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 14.98
Number of options outstanding (in shares)	986,100
Weighted-average remaining contractual life	3 years
Number of options exercisable (in shares)	657,393
December 17, 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 14.43
Number of options outstanding (in shares)	871,800
Weighted-average remaining contractual life	4 years
Number of options exercisable (in shares)	290,597
January 4, 2021 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 14.07
Number of options outstanding (in shares)	10,000
Weighted-average remaining contractual life	4 years
Number of options exercisable (in shares)	3,333
December 16, 2021 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options [Abstract]
Exercise price (in dollars per share)	$ 14.39
Number of options outstanding (in shares)	895,300
Weighted-average remaining contractual life	5 years
Number of options exercisable (in shares)	0