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Fair Values of Assets and Liabilities - Schedule of Balances of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | $ 4,885,715 |  | $ 4,141,482 | $ 4,329,957 |  |
Equity securities with readily determinable fair value | 273,722 |  | 215,412 | 112,173 |  |
Loans held-for-investment | 136,884 |  |  | 135,834 |  |
MSRs | 193,061 | $ 196,307 | 203,788 | 204,610 | $ 201,044 | $ 192,456
U.S. Treasury |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 13,018 |  | 37,907 | 102,712 |  |
U.S. government agencies |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 45,824 |  | 44,945 | 45,192 |  |
Municipal |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 180,644 |  | 184,593 | 146,608 |  |
Measured at fair value on a recurring basis: |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Trading account securities | 0 |  | 4,072 | 4,134 |  |
Equity securities with readily determinable fair value | 273,722 |  | 215,412 | 112,173 |  |
Mortgage loans held-for-sale | 299,606 |  | 331,261 | 411,851 |  |
Loans held-for-investment | 136,884 |  | 158,795 | 135,834 |  |
MSRs | 193,061 |  | 203,788 | 204,610 |  |
Nonqualified deferred compensation assets | 17,283 |  | 16,653 | 16,041 |  |
Derivative assets | 221,106 |  | 200,027 | 243,860 |  |
Total | 6,027,377 |  | 5,271,490 | 5,458,460 |  |
Derivative liabilities | 161,402 |  | 241,750 | 317,659 |  |
Measured at fair value on a recurring basis: | Level 1 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Trading account securities | 0 |  | 0 | 0 |  |
Equity securities with readily determinable fair value | 265,656 |  | 207,346 | 104,107 |  |
Mortgage loans held-for-sale | 0 |  | 0 | 0 |  |
Loans held-for-investment | 0 |  | 0 | 0 |  |
MSRs | 0 |  | 0 | 0 |  |
Nonqualified deferred compensation assets | 0 |  | 0 | 0 |  |
Derivative assets | 0 |  | 0 | 0 |  |
Total | 278,674 |  | 245,253 | 206,819 |  |
Derivative liabilities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | Level 2 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Trading account securities | 0 |  | 4,072 | 4,134 |  |
Equity securities with readily determinable fair value | 8,066 |  | 8,066 | 8,066 |  |
Mortgage loans held-for-sale | 272,438 |  | 270,862 | 371,306 |  |
Loans held-for-investment | 83,847 |  | 123,899 | 90,113 |  |
MSRs | 0 |  | 0 | 0 |  |
Nonqualified deferred compensation assets | 17,283 |  | 16,653 | 16,041 |  |
Derivative assets | 215,558 |  | 198,077 | 239,065 |  |
Total | 5,353,814 |  | 4,603,597 | 4,860,178 |  |
Derivative liabilities | 161,402 |  | 241,750 | 317,659 |  |
Measured at fair value on a recurring basis: | Level 3 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Trading account securities | 0 |  | 0 | 0 |  |
Equity securities with readily determinable fair value | 0 |  | 0 | 0 |  |
Mortgage loans held-for-sale | 27,168 |  | 60,399 | 40,545 |  |
Loans held-for-investment | 53,037 |  | 34,896 | 45,721 |  |
MSRs | 193,061 |  | 203,788 | 204,610 |  |
Nonqualified deferred compensation assets | 0 |  | 0 | 0 |  |
Derivative assets | 5,548 |  | 1,950 | 4,795 |  |
Total | 394,889 |  | 422,640 | 391,463 |  |
Derivative liabilities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | U.S. Treasury |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 13,018 |  | 37,907 | 102,712 |  |
Measured at fair value on a recurring basis: | U.S. Treasury | Level 1 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 13,018 |  | 37,907 | 102,712 |  |
Measured at fair value on a recurring basis: | U.S. Treasury | Level 2 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | U.S. Treasury | Level 3 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | U.S. government agencies |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 45,824 |  | 44,945 | 45,192 |  |
Measured at fair value on a recurring basis: | U.S. government agencies | Level 1 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | U.S. government agencies | Level 2 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 45,824 |  | 44,945 | 45,192 |  |
Measured at fair value on a recurring basis: | U.S. government agencies | Level 3 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | Municipal |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 180,644 |  | 184,593 | 146,608 |  |
Measured at fair value on a recurring basis: | Municipal | Level 1 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | Municipal | Level 2 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 64,569 |  | 62,986 | 50,816 |  |
Measured at fair value on a recurring basis: | Municipal | Level 3 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 116,075 |  | 121,607 | 95,792 |  |
Measured at fair value on a recurring basis: | Corporate notes |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 79,799 |  | 81,162 | 77,975 |  |
Measured at fair value on a recurring basis: | Corporate notes | Level 1 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | Corporate notes | Level 2 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 79,799 |  | 81,162 | 77,975 |  |
Measured at fair value on a recurring basis: | Corporate notes | Level 3 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | Mortgage-backed |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 4,566,430 |  | 3,792,875 | 3,957,470 |  |
Measured at fair value on a recurring basis: | Mortgage-backed | Level 1 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 0 |  | 0 | 0 |  |
Measured at fair value on a recurring basis: | Mortgage-backed | Level 2 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | 4,566,430 |  | 3,792,875 | 3,957,470 |  |
Measured at fair value on a recurring basis: | Mortgage-backed | Level 3 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Available-for-sale securities | $ 0 |  | $ 0 | $ 0 |  |

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