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Investment Securities (Schedule of the Aggregate Fair Value and Amount by which Amortized Cost Exceeds Fair Value for Investment Securities that are in Unrealized Loss Positions) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 1,657,440 | $ 1,622,289
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 7,569 | 11,807
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 4,093,369 | 5,115,305
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 339,624 | 402,194
Debt Securities, Available-for-sale, Unrealized Loss Position | 5,750,809 | 6,737,594
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 347,193 | 414,001
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 53,724 | 126,710
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 1,442 | 3,195
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 42,776 | 40,791
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 6,862 | 8,814
Debt Securities, Available-for-sale, Unrealized Loss Position | 96,500 | 167,501
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 8,304 | 12,009
U.S. Government agency and sponsored enterprise residential MBS |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 334,189 | 895,759
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 2,077 | 5,474
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 711,375 | 936,106
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 17,191 | 20,997
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,045,564 | 1,831,865
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 19,268 | 26,471
U.S. Government agency and sponsored enterprise commercial MBS |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 37,967 | 55,431
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 376 | 1,545
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 401,394 | 394,735
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 48,151 | 60,347
Debt Securities, Available-for-sale, Unrealized Loss Position | 439,361 | 450,166
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 48,527 | 61,892
Private label residential MBS and CMOs |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 201,978 | 147,700
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 1,503 | 954
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,967,841 | 2,040,335
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 225,004 | 252,539
Debt Securities, Available-for-sale, Unrealized Loss Position | 2,169,819 | 2,188,035
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 226,507 | 253,493
Private label commercial MBS |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 440,202 | 44,000
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 1,056 | 302
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 633,038 | 1,199,150
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 26,621 | 40,386
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,073,240 | 1,243,150
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 27,677 | 40,688
Single family real estate-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 156,151 | 301,973
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 4,193 | 8,074
Debt Securities, Available-for-sale, Unrealized Loss Position | 156,151 | 301,973
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 4,193 | 8,074
Collateralized loan obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 573,567 | 336,924
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 1,043 | 189
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 7,726
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 4
Debt Securities, Available-for-sale, Unrealized Loss Position | 573,567 | 344,650
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 1,043 | 193
Non-mortgage asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 68,714 | 71,789
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 1,699 | 2,555
Debt Securities, Available-for-sale, Unrealized Loss Position | 68,714 | 71,789
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 1,699 | 2,555
State and municipal obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 15,813 | 15,765
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 72 | 148
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 51,218 | 54,820
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 8,002 | 6,243
Debt Securities, Available-for-sale, Unrealized Loss Position | 67,031 | 70,585
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 8,074 | 6,391
SBA securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 60,862 | 67,880
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 1,901 | 2,235
Debt Securities, Available-for-sale, Unrealized Loss Position | 60,862 | 67,880
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ 1,901 | $ 2,235

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