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Capital Stock (Details) - USD ($) $ in Millions |  | 3 Months Ended |
--- | --- | --- | ---
Feb. 01, 2022 | Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Class of Stock [Line Items] |  |  |  |
Shares outstanding (in shares) |  | 104,382,018 |  | 104,442,023
Common shares issued (in shares) |  |  | 46,887,104 |
Stock repurchased and retired (in shares) |  | 55,080 | 37,698 |
Stock Repurchased and Retired During Period, Value |  | $ 1.8 | $ 1.4 |
Common Stock, Shares, Issued |  | 104,382,018 |  | 104,442,023
Great Western Bank |  |  |  |
Class of Stock [Line Items] |  |  |  |
Total consideration exchanged | $ 1,723.3 |  |  |
Class A Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares outstanding (in shares) |  |  |  | 104,442,023
Common Stock, Shares, Issued |  |  |  | 104,442,023
Class A Common Stock | Great Western Bank |  |  |  |
Class of Stock [Line Items] |  |  |  |
Number of shares issued as consideration (in shares) | 46,900,000 |  |  |

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