Stock Based Compensation - Exercise Price Range (Details) - $ / shares	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of Options, Outstanding (in shares)	252,500	407,500	107,500
Weighted Average Remaining Contractual Life (In Years)	5 years 9 months 29 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 9.69	$ 7.57	$ 19.64
Number of Options, Exercisable (in shares)	102,500	107,500	107,500
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 19.13	$ 19.64	$ 19.64
$0.00 – $10.00
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of price, lower range limit (in dollars per share)	0.00
Range of price, upper range limit (in dollars per share)	$ 10.00
Number of Options, Outstanding (in shares)	152,500
Weighted Average Remaining Contractual Life (In Years)	9 years 1 month 17 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 3.34
Number of Options, Exercisable (in shares)	2,500
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 1.20
$10.01 – $20.00
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of price, lower range limit (in dollars per share)	10.01
Range of price, upper range limit (in dollars per share)	$ 20.00
Number of Options, Outstanding (in shares)	97,500
Weighted Average Remaining Contractual Life (In Years)	9 months 21 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 19.32
Number of Options, Exercisable (in shares)	97,500
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 19.32
$20.01 – $30.00
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Range of price, lower range limit (in dollars per share)	20.01
Range of price, upper range limit (in dollars per share)	$ 30.00
Number of Options, Outstanding (in shares)	2,500
Weighted Average Remaining Contractual Life (In Years)	2 months 8 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 21.80
Number of Options, Exercisable (in shares)	2,500
Exercisable Weighted Average Exercise Price (in dollars per share)	$ 21.80

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.

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

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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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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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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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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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