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Stockholders' Equity and Earnings Per Common Share - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
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Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Stockholders Equity and Earnings Per Common Share Additional Information [Abstract] |  |  |  |  |  |
Outstanding Restricted Stock and Stock Success Unit Grant Prices Lower Limit | $ 18.78 |  |  | $ 18.78 |  |
Outstanding Restricted Stock and Stock Success Unit Grant Prices Upper Limit | $ 52.40 |  |  | $ 52.40 |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share |  |  | 800,000 | 300,000 |  | 700,000
Cost of Shares Repurchased | $ 179.8 | [1] | $ 47.0 | $ 302.8 | [1] | $ 100.6
Number of Treasury Shares Repurchased | 3,500,000 |  | 1,100,000 | 6,000,000.0 |  | 2,400,000
Authorized Shares of Preferred Stock | 25,000,000.0 |  |  | 25,000,000.0 |  |
Par Value Per Share of Preferred Stock | $ 0.10 |  |  | $ 0.10 |  |
Issued Shares of Preferred Stock | 0 |  |  | 0 |  |
[1] | 1Includes a de minimis amount of commissions for the three and six months ended June 30, 2024 and $0.1 million of commissions for the three and six months ended June 30, 2023. Also includes $1.7 million and $2.8 million of excise tax for the three and six months ended June 30, 2024, respectively, and $0.4 million and $0.5 million of excise tax for the three and six months ended June 30, 2023, respectively.

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 260 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482662/260-10-50-1 + Details
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