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Equity and Financing Arrangements (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2021 | Sep. 30, 2020 | Aug. 27, 2021 | Jun. 15, 2021
Common Stock [Abstract] |  |  |  |  |
Common stock issued during period |  |  | 1,500,000 |  |
Common stock issued during period under the stock plan | 0 | 0 |  |  |
Issuance of common stock, net |  | $ 0 | $ 79,635 |  |
Dilutive Shares Calculation [Abstract] |  |  |  |  |
Shares included in diluted earnings per share |  | 13,021 |  |  |
Debt Issuance, 2.48% due 2031 | Other Long-Term Debt [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Face amount |  |  |  | $ 60,000 |
Interest rate |  |  |  | 2.48% |
Term |  | 10 years |  |  |
Debt Issuance, 2.63% due 2033 | Other Long-Term Debt [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Face amount |  |  |  |  | $ 40,000
Interest rate |  |  |  |  | 2.63%
Term |  | 12 years |  |  |

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