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Financing Arrangements - Narrative (Details) $ / shares in Units, shares in Millions |  |  | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 01, 2025 USD ($) shares | Dec. 15, 2020 USD ($) $ / shares | Dec. 31, 2024 USD ($) | Mar. 31, 2023 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2024 USD ($) Days shares | Dec. 31, 2023 USD ($) shares | Dec. 31, 2022 USD ($) shares | Feb. 17, 2025 USD ($) | May 06, 2024 USD ($) | Nov. 02, 2022 USD ($) | Dec. 20, 2021 shares
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] |  |  |  |  |  | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] |  |  |  |  |  |
Variable interest rate, spread |  |  |  |  |  | 0.00% |  |  |  |  |  |
Settled with cash payment |  |  |  |  |  | $ 17,200,000 | $ 18,700,000 | $ 67,600,000 |  |  |  |
Loss on extinguishment of debt |  |  |  |  |  | 9,400,000 | 11,400,000 | 43,100,000 |  |  |  |
Interest paid |  |  |  |  |  | 2,000,000 | 2,100,000 | 3,100,000 |  |  |  |
Money market investment carrying value |  |  | $ 110,200,000 |  |  | 110,200,000 | 139,700,000 | $ 209,500,000 |  |  |  |
Cash Held In Other Investments |  |  | 125,400,000 |  |  | 125,400,000 | 119,900,000 |  |  |  |  |
Common Stock, Shares outstanding | shares |  |  |  |  |  |  |  |  |  |  |  | 50.0
Stock Repurchase Program, Amount |  |  |  |  |  |  |  |  |  |  | $ 75,000,000 |
Average Repurchase price |  |  |  |  |  | $ 18.45 | $ 19.03 |  |  |  |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Amount |  |  |  |  |  |  |  |  |  | $ 100,000,000 |  |
Stock Repurchased, Shares | shares |  |  |  |  |  | 2.0 | 1.7 | 3.0 |  |  |  |
Stock Repurchased, Amount |  |  |  |  |  | $ 37,600,000 | $ 32,600,000 | $ 52,000,000 |  |  |  |
Average Repurchase price |  |  |  |  |  |  |  | 17.18 |  |  |  |
Stock Repurchase Program, Remaining Amount |  |  | 102,800,000 |  |  | $ 102,800,000 |  |  |  |  |  |
Subsequent Event | Common Shares |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased, Shares | shares | 0.2 |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased, Amount | $ 3,300,000 |  |  |  |  |  |  |  |  |  |  |
Average Repurchase price | $ 14.61 |  |  |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Remaining Amount |  |  |  |  |  |  |  |  | $ 99,500,000 |  |  |
Third Amended Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  | Sep. 30, 2027 |  |  |  |  |  |
Third Amended Credit Facility | Credit Agreement |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, tentative future commitment increase |  |  | 217,900,000 |  |  | $ 217,900,000 |  |  |  |  |  |
Fourth Amended Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  | 400,000,000 |  |  | 400,000,000 |  |  |  |  |  |
Line of credit facility, tentative future commitment increase |  |  | 100,000,000 |  |  | $ 100,000,000 |  |  |  |  |  |
Variable interest rate, spread |  |  |  |  |  | 1.00% |  |  |  |  |  |
Line of credit facility, unused capacity, commitment fee percentage |  |  |  |  |  | 0.25% |  |  |  |  |  |
Fourth Amended Credit Facility | Commercial and Standby Letters of Credit |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, borrowing sublimit |  |  | 15,000,000 |  |  | $ 15,000,000 |  |  |  |  |  |
Fourth Amended Credit Facility | Swingline Loans |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, borrowing sublimit |  |  | 40,000,000 |  |  | 40,000,000 |  |  |  |  |  |
Fourth Amended Credit Facility | First In, Last Out (FILO) |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, tentative future commitment increase |  |  | 30,000,000 |  |  | $ 30,000,000 |  |  |  |  |  |
Convertible Senior Notes due 2025 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  | Dec. 01, 2025 |  |  |  |  |  |  |  |  |  |
Terms of conversion |  |  |  |  |  | The Convertible Senior Notes due 2025 are convertible at the option of the holders in certain circumstances and during certain periods into the Company's common shares, cash, or a combination thereof, at the Company's election. |  |  |  |  |  |
Principal amount |  |  | 5,500,000 |  |  | $ 5,500,000 |  | 0 |  |  |  |
Principal amount, repurchased |  |  | 7,800,000 | $ 7,500,000 | $ 25,200,000 | $ 7,800,000 |  |  |  |  |  |
Settled with cash payment |  |  | 17,200,000 | 18,700,000 | 67,600,000 |  |  |  |  |  |  |
Debt instrument, threshold trading days | Days |  |  |  |  |  | 20 |  |  |  |  |  |
Debt Instrument, threshold consecutive trading days | Days |  |  |  |  |  | 30 |  |  |  |  |  |
Debt Instrument, threshold Percentage of stock price conversion |  |  |  |  |  | 130.00% |  |  |  |  |  |
Loss on extinguishment of debt |  |  | 9,400,000 | 11,400,000 | 43,000,000 |  |  |  |  |  |  |
Unamortized debt issuance costs |  |  | 100,000 | $ 200,000 | $ 600,000 | $ 100,000 |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  | 6.00% |  |  |  |  |  |  |  |  |  |
Debt instrument interest payment dates description |  | June 1 and December 1 of each year, beginning on December 1, 2021 |  |  |  |  |  |  |  |  |  |
Debt instrument, convertible, conversion price | $ / shares |  | $ 7.82 |  |  |  |  |  |  |  |  |  |
Debt instrument, convertible, conversion ratio |  | 0.1278119 |  |  |  |  |  |  |  |  |  |
Debt instrument, convertible, amounts by which instrument can be converted |  | $ 1,000 |  |  |  |  |  |  |  |  |  |
Transaction costs, debt gross |  |  | 1,500,000 |  |  | 1,500,000 |  |  |  |  |  |
Fair value of convertible notes |  |  | 10,200,000 |  |  | 10,200,000 | 41,500,000 |  |  |  |  |
Outstanding borrowings |  |  | $ 0 |  |  | $ 0 | $ 0 | $ 0 |  |  |  |

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