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Nature of Operations And Basis of Presentation (Details) | Nov. 11, 2020 | Dec. 31, 2020 USD ($) | Feb. 07, 2020 USD ($) | Dec. 31, 2019
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Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Stock dividend | 50.00% |  |  |
Stock split description | On November 11, 2020, our Board approved a 50% stock dividend, in the form of a three-for-two stock split, of our common stock payable on December 16, 2020, to shareholders of record as of December 2, 2020. All share and per share information has been retroactively adjusted to reflect the stock split. |  |  |
Stock split, conversion ratio | 1.5 |  |  |
Stifel Credit Facility [Member] |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Credit facility |  | $ 300,000,000.0 |  |
North Shore Aviation Holdings LLC [Member] |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Noncontrolling Interest, Ownership Percentage by Parent |  |  |  | 27.50%
North Shore Aviation Holdings LLC [Member] | Stifel Credit Facility [Member] |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |
Credit facility |  |  | $ 120,000,000.0 |

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