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Stock-Based Compensation Plans (Narrative) (Details) | 3 Months Ended
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Mar. 31, 2021 USD ($) plan shares | Mar. 31, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Compensation expense for share-based payments | $ 5,894,645 | $ 6,356,070
Omnibus Incentive Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares issued under the Omnibus plan | shares | 11,238,857 |
Employee Stock Option Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Unrecognized compensation cost | $ 7,524,575 |
Employee Stock Option Plan | Minimum |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Option vesting period | 1 year |
Option expiration period | 5 years |
Employee Stock Option Plan | Maximum |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Option vesting period | 5 years |
Option expiration period | 10 years |
Restricted Stock Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Unrecognized compensation cost | $ 39,260,117 |
Restricted period, maximum | 10 years |
Amortization expense | $ 4,302,975 | 4,362,318
Employee Stock Purchase Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares approved | shares | 2,000,000 |
ESPP discount rate | 85.00% |
ESPP discount rate recognized as compensation expense | 15.00% |
Shares granted (in shares) | shares | 1,386,879 |
Equity Incentive Plans |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of plans | plan | 2 |
Performance Shares |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Unrecognized compensation cost | $ 11,273,771 |
Amortization expense | $ 104,231 | $ 393,777

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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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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 + Details
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