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Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | $ 9,493,179 | $ 9,215,376
Financial and Nonfinancial Liabilities, Fair Value Disclosure | (85,573) |
Derivative Financial Instruments, Liabilities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Financial and Nonfinancial Liabilities, Fair Value Disclosure | (85,573) | (85,899)
U.S. Treasury securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 142,569 | 202,952
U.S. Government agency and sponsored enterprise residential MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 2,712,538 | 2,649,690
U.S. Government agency and sponsored enterprise commercial MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 500,325 | 495,753
Private label residential MBS and CMOs |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 2,361,504 | 2,238,046
Private label commercial MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 2,095,039 | 1,784,029
Single family real estate-backed securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 203,353 | 327,081
Collateralized loan obligations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 1,118,831 | 1,132,699
Non-mortgage asset-backed securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 89,790 | 94,454
State and municipal obligations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 103,874 | 104,010
SBA securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 64,569 | 72,702
Marketable equity securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 8,679 | 28,828
Derivative Financial Instruments, Assets [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 92,108 | 85,132
Fair Value, Inputs, Level 1 |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 151,248 | 231,780
Financial and Nonfinancial Liabilities, Fair Value Disclosure | 0 |
Fair Value, Inputs, Level 1 | Derivative Financial Instruments, Liabilities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Financial and Nonfinancial Liabilities, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | U.S. Treasury securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 142,569 | 202,952
Fair Value, Inputs, Level 1 | U.S. Government agency and sponsored enterprise residential MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | U.S. Government agency and sponsored enterprise commercial MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | Private label residential MBS and CMOs |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | Private label commercial MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | Single family real estate-backed securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | Collateralized loan obligations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | Non-mortgage asset-backed securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | State and municipal obligations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | SBA securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 | Marketable equity securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 8,679 | 28,828
Fair Value, Inputs, Level 1 | Derivative Financial Instruments, Assets [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 2 |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 9,341,931 | 8,983,596
Financial and Nonfinancial Liabilities, Fair Value Disclosure | (85,573) |
Fair Value, Inputs, Level 2 | Derivative Financial Instruments, Liabilities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Financial and Nonfinancial Liabilities, Fair Value Disclosure | (85,573) | (85,899)
Fair Value, Inputs, Level 2 | U.S. Treasury securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 2 | U.S. Government agency and sponsored enterprise residential MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 2,712,538 | 2,649,690
Fair Value, Inputs, Level 2 | U.S. Government agency and sponsored enterprise commercial MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 500,325 | 495,753
Fair Value, Inputs, Level 2 | Private label residential MBS and CMOs |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 2,361,504 | 2,238,046
Fair Value, Inputs, Level 2 | Private label commercial MBS |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 2,095,039 | 1,784,029
Fair Value, Inputs, Level 2 | Single family real estate-backed securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 203,353 | 327,081
Fair Value, Inputs, Level 2 | Collateralized loan obligations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 1,118,831 | 1,132,699
Fair Value, Inputs, Level 2 | Non-mortgage asset-backed securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 89,790 | 94,454
Fair Value, Inputs, Level 2 | State and municipal obligations |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 103,874 | 104,010
Fair Value, Inputs, Level 2 | SBA securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 64,569 | 72,702
Fair Value, Inputs, Level 2 | Marketable equity securities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 2 | Derivative Financial Instruments, Assets [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | $ 92,108 | $ 85,132

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