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Fair Value Measurements - Summary of Fair Values of Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value | [1] | $ 9,006,600 | $ 8,959,729
Total derivative instruments, after netting |  | 19,049 | 42,497
Originated loans held for sale |  | $ 297 | 2,610
Derivative Liability Statement Of Financial Position Extensible Enumeration Not Disclosed Flag |  | true |
Derivative Liability |  | $ 279,600 | 279,861
Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 9,006,600 | 8,959,729
Alternative investments |  |  | 959
Alternative investments measured at NAV |  | 43,360 | 35,888
Total financial assets |  | 9,365,837 | 9,341,722
Derivative Liability |  | 311,561 | 335,810
Contingent consideration |  | 11,750 | 15,800
Total financial liabilities |  | 323,311 | 351,610
Fair Value, Recurring | Derivative instruments |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total derivative instruments, after netting |  | 302,142 | 330,636
Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Alternative investments |  |  | 959
Alternative investments measured at NAV |  | 0 | 0
Total financial assets |  | 14,701 | 13,076
Derivative Liability |  | 43 | 970
Contingent consideration |  | 0 | 0
Total financial liabilities |  | 43 | 970
Fair Value, Recurring | Level 1 | Derivative instruments |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total derivative instruments, after netting |  | 1,263 | 217
Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 9,006,600 | 8,959,729
Alternative investments |  |  | 0
Alternative investments measured at NAV |  | 0 | 0
Total financial assets |  | 9,307,776 | 9,292,758
Derivative Liability |  | 311,518 | 334,840
Contingent consideration |  | 0 | 0
Total financial liabilities |  | 311,518 | 334,840
Fair Value, Recurring | Level 2 | Derivative instruments |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total derivative instruments, after netting |  | 300,879 | 330,419
Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Alternative investments |  |  | 0
Alternative investments measured at NAV |  | 0 | 0
Total financial assets |  | 0 | 0
Derivative Liability |  | 0 | 0
Contingent consideration |  | 11,750 | 15,800
Total financial liabilities |  | 11,750 | 15,800
Fair Value, Recurring | Level 3 | Derivative instruments |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total derivative instruments, after netting |  | 0 | 0
Originated loans held for sale | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Originated loans held for sale |  | 297 | 2,610
Originated loans held for sale | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Originated loans held for sale |  | 0 | 0
Originated loans held for sale | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Originated loans held for sale |  | 297 | 2,610
Originated loans held for sale | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Originated loans held for sale |  | 0 | 0
Investments held in Rabbi Trusts | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments held in Rabbi Trust |  | 13,438 | 11,900
Investments held in Rabbi Trusts | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments held in Rabbi Trust |  | 13,438 | 11,900
Investments held in Rabbi Trusts | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments held in Rabbi Trust |  | 0 | 0
Investments held in Rabbi Trusts | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments held in Rabbi Trust |  | 0 | 0
Government agency debentures |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 186,426 | 264,633
Government agency debentures | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 186,426 | 264,633
Government agency debentures | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Government agency debentures | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 186,426 | 264,633
Government agency debentures | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Municipal bonds and notes |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 110,876 | 1,573,233
Municipal bonds and notes | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 110,876 | 1,573,233
Municipal bonds and notes | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Municipal bonds and notes | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 110,876 | 1,573,233
Municipal bonds and notes | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Agency CMO |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 29,043 | 48,941
Agency CMO | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 29,043 | 48,941
Agency CMO | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Agency CMO | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 29,043 | 48,941
Agency CMO | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Agency MBS |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 4,519,785 | 3,347,098
Agency MBS | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 4,519,785 | 3,347,098
Agency MBS | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Agency MBS | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 4,519,785 | 3,347,098
Agency MBS | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Agency CMBS |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 3,034,392 | 2,288,071
Agency CMBS | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 3,034,392 | 2,288,071
Agency CMBS | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Agency CMBS | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 3,034,392 | 2,288,071
Agency CMBS | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
CMBS |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 625,388 | 763,749
CMBS | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 625,388 | 763,749
CMBS | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
CMBS | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 625,388 | 763,749
CMBS | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Corporate debt |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 452,266 | 622,155
Corporate debt | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 452,266 | 622,155
Corporate debt | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Corporate debt | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 452,266 | 622,155
Corporate debt | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Private label MBS |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 39,219 | 42,808
Private label MBS | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 39,219 | 42,808
Private label MBS | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Private label MBS | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 39,219 | 42,808
Private label MBS | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Other |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 9,205 | 9,041
Other | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 9,205 | 9,041
Other | Fair Value, Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 0 | 0
Other | Fair Value, Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | 9,205 | 9,041
Other | Fair Value, Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investment securities available-for-sale, at fair value |  | $ 0 | $ 0
[1] | Investment securities available-for-sale had an amortized cost basis of $9,720,415 at December 31, 2024, and $9,668,422 at December 31, 2023.

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- Definition Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 107 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-107 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 103 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-103 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 100 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-100 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 35 -Paragraph 54B -Publisher FASB -URI https://asc.fasb.org/1943274/2147482134/820-10-35-54B Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. 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