Compensation Plans - Textual (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 5,200,000	$ 5,200,000	$ 3,300,000
Deferred compensation equity	15,268,705	14,748,118
Proceeds received under employee stock purchase plan	$ 603,268	0	$ 0
Deferred compensation arrangement, fully vested employee elected deferral period	5 years
Deferred compensation liability, current and noncurrent	$ 37,348,294	$ 33,241,952
401K
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of years of employment required to vest in contribution	6 years
2011 Equity and Cash Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorizes the issuance of Common Shares in various forms of equity awards (in shares)	600,000
Common Shares available for awards (in shares)	179,001
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants issued (in dollars per share)	$ 158.92	$ 115.32	$ 146.59
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorizes the issuance of Common Shares in various forms of equity awards (in shares)	95,722
ESPP shares purchased during year (in shares)	4,278
Proceeds received under employee stock purchase plan	$ 600,000
Share based payment expense	$ 100,000

Deferred Compensation Arrangement, Fully Vested Employee Elected Deferral Period, Minimum

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Number years of service required of employees to vest in contribution.

+ References

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Proceeds Received Under Employee Stock Purchase Plan

+ References

No definition available.

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- Definition

Amount of increase to additional paid-in capital (APIC) for recognition of cost for option under share-based payment arrangement.

+ References

No definition available.

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- Definition

Value of stock issued under share-based plans to employees or officers which is the unearned portion, accounted for under the fair value method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 35
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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares issued under share-based payment arrangement.

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