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Debt (Narrative) (Details) - USD ($) $ in Millions | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Senior Notes [Member] | 3.6% senior notes, due 2032 [Member] |  |
Debt [Line Items] |  |
Long-term debt | $ 350 |
Interest rate, percent | 3.60% |
Term Loan Credit Agreement [Member] | Term loan credit agreement through March 2024 |  |
Debt [Line Items] |  |
Long-term debt | $ 300 |
Interest rate, percent | 1.00% |
Term Loan Credit Agreement [Member] | Term loan credit agreement through March 2022 |  |
Debt [Line Items] |  |
Long-term debt |  | $ 300

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