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Shareholders' Equity And Earnings Per Share (Narrative) (Detail) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
May 31, 2020 | Jun. 30, 2015 | Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2022 | Dec. 31, 2021
Temporary Equity [Line Items] |  |  |  |  |  |
Cash dividends declared per common share (usd per share) |  |  | $ 0.34 | $ 0.31 |  |
Forecast |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Cash dividends declared per common share (usd per share) |  |  |  |  | $ 1.36 |
Series D Preferred Stock |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Sale of stock (in shares) |  | 5,000,000 |  |  |  |
Preferred stock, liquidation value per share (usd per share) |  | $ 25 | 25 | 25 |  | $ 25
Sale of stock, proceeds |  | $ 125.0 |  |  |  |
Preferred stock, dividend rate, percentage |  | 6.50% |  |  |  |
Series D Preferred Stock | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Preferred stock, dividend rate, percentage, variable spread |  | 4.06% |  |  |  |
Series E Preferred Stock |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Sale of stock (in shares) | 11,500 |  |  |  |  |
Preferred stock, liquidation value per share (usd per share) | $ 25,000 |  | $ 25,000 | $ 25,000 |  | $ 25,000
Sale of stock, proceeds | $ 287.5 |  |  |  |  |
Preferred stock, dividend rate, percentage | 6.875% |  |  |  |  |
Series E Preferred Stock | US Treasury (UST) Interest Rate |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Dividend rate, spread on floating rate | 0.06507 |  |  |  |  |
6.875% Fixed-Rate Reset Non-Cumulative Perpetual Preferred Stock, Series E, no par value |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |
Sale of stock (in shares) | 11,500,000 |  |  |  |  |

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