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Allowance for Credit Losses and Unfunded Loan Commitments - Loan Portfolio Stratified by Key Credit Quality Indicators (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
% of Balance |  |  |
Current period recoveries, total | $ (377,220) | $ (421,096) | $ (431,244)
Current period recoveries, total | 44,756 | 46,368 | 41,742
Current period net charge-offs, total | (332,464) | (374,728) | (389,502)
Consumer Portfolio Segment | Student Loan |  |  |
% of Balance |  |  |
Current period gross charge-offs, Year 1 | (1,826) | (1,812) |
Current period gross charge-offs, Year 2 | (29,094) | (31,032) |
Current period gross charge-offs, Year 3 | (68,454) | (70,331) |
Current period gross charge-offs, Year 4 | (53,697) | (49,624) |
Current period gross charge-offs, Year 5 | (37,318) | (50,585) |
Current period gross charge-offs, Year 6 | (186,451) | (216,711) |
Current period recoveries, total | (376,840) | (420,095) |
Current period recoveries, Year 1 | 117 | 172 |
Current period recoveries, Year 2 | 2,191 | 2,342 |
Current period recoveries, Year 3 | 6,487 | 6,496 |
Current period recoveries, Year 4 | 5,771 | 4,923 |
Current period recoveries, Year 5 | 3,840 | 5,260 |
Current period recoveries, Year 6 | 26,350 | 27,175 |
Current period recoveries, total | 44,756 | 46,368 |
Current period net charge-offs, Year 1 | (1,709) | (1,640) |
Current period net charge-offs, Year 2 | (26,903) | (28,690) |
Current period net charge-offs, Year 3 | (61,967) | (63,835) |
Current period net charge-offs, Year 4 | (47,926) | (44,701) |
Current period net charge-offs, Year 5 | (33,478) | (45,325) |
Current period net charge-offs, Year 6 | (160,101) | (189,536) |
Current period net charge-offs, total | (332,084) | (373,727) |
Total accrued interest by origination vintage, Year 1 | 195,291 | 177,959 |
Total accrued interest by origination vintage, Year 2 | 484,531 | 408,800 |
Total accrued interest by origination vintage, Year 3 | 325,962 | 269,978 |
Total accrued interest by origination vintage, Year 4 | 197,504 | 152,094 |
Total accrued interest by origination vintage, Year 5 | 106,565 | 116,618 |
Total accrued interest by origination vintage, Year 6 | 239,562 | 229,116 |
Total accrued interest by origination vintage | 1,549,415 | 1,354,565 |
Consumer Portfolio Segment | Student Loan | Loan delinquent, current |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | 2,820,940 | 2,469,817 | 2,411,441
Year 2 | 3,312,916 | 3,254,534 | 2,991,839
Year 3 | 2,259,455 | 2,131,040 | 1,907,574
Year 4 | 1,590,812 | 1,416,069 | 1,683,986
Year 5 | 1,107,189 | 1,323,825 | 1,301,809
After Year 5 | 4,422,021 | 4,213,986 | 4,262,698
Loan type | 15,513,333 | 14,809,271 | 14,559,347
Consumer Portfolio Segment | Student Loan | Loan delinquent 30-59 days |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | 13,533 | 17,599 | 14,164
Year 2 | 36,441 | 34,627 | 30,740
Year 3 | 45,543 | 37,147 | 30,877
Year 4 | 35,245 | 28,020 | 35,213
Year 5 | 27,302 | 31,432 | 31,366
After Year 5 | 152,684 | 149,926 | 144,948
Loan type | 310,748 | 298,751 | 287,308
Consumer Portfolio Segment | Student Loan | Loan delinquent 60-89 days |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | 3,973 | 5,720 | 5,523
Year 2 | 15,239 | 17,227 | 15,056
Year 3 | 23,359 | 20,077 | 14,433
Year 4 | 18,365 | 16,614 | 18,201
Year 5 | 10,921 | 15,482 | 16,697
After Year 5 | 68,878 | 75,897 | 77,595
Loan type | 140,735 | 151,017 | 147,505
Consumer Portfolio Segment | Student Loan | Loan delinquent 90 days or greater past due |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | 1,683 | 1,678 | 1,710
Year 2 | 14,481 | 16,939 | 11,842
Year 3 | 20,147 | 21,470 | 14,872
Year 4 | 17,080 | 15,155 | 16,819
Year 5 | 12,632 | 16,150 | 16,107
After Year 5 | 75,912 | 79,383 | 74,040
Loan type | 141,935 | 150,775 | $ 135,390
Consumer Portfolio Segment | Student Loan | With and without cosigners |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | 5,024,592 | 4,490,119 |
Year 2 | 5,321,510 | 5,088,739 |
Year 3 | 3,185,247 | 2,937,422 |
Year 4 | 2,069,436 | 1,819,089 |
Year 5 | 1,373,996 | 1,632,300 |
After Year 5 | 5,260,227 | 5,058,175 |
Loan type | $ 22,235,008 | $ 21,025,844 |
% of Balance |  |  |
Total in percent | 100.00% | 100.00% |
Consumer Portfolio Segment | Student Loan | With cosigner |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 4,519,952 | $ 3,903,676 |
Year 2 | 4,707,685 | 4,428,163 |
Year 3 | 2,741,871 | 2,516,380 |
Year 4 | 1,759,261 | 1,535,308 |
Year 5 | 1,151,751 | 1,378,699 |
After Year 5 | 4,642,019 | 4,529,768 |
Loan type | $ 19,522,539 | $ 18,291,994 |
% of Balance |  |  |
Private education loans | 88.00% | 87.00% |
Consumer Portfolio Segment | Student Loan | Without cosigner |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 504,640 | $ 586,443 |
Year 2 | 613,825 | 660,576 |
Year 3 | 443,376 | 421,042 |
Year 4 | 310,175 | 283,781 |
Year 5 | 222,245 | 253,601 |
After Year 5 | 618,208 | 528,407 |
Loan type | $ 2,712,469 | $ 2,733,850 |
% of Balance |  |  |
Private education loans | 12.00% | 13.00% |
Consumer Portfolio Segment | Student Loan | FICO at Origination |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 5,024,592 | $ 4,490,119 |
Year 2 | 5,321,510 | 5,088,739 |
Year 3 | 3,185,247 | 2,937,422 |
Year 4 | 2,069,436 | 1,819,089 |
Year 5 | 1,373,996 | 1,632,300 |
After Year 5 | 5,260,227 | 5,058,175 |
Loan type | $ 22,235,008 | $ 21,025,844 |
% of Balance |  |  |
Total in percent | 100.00% | 100.00% |
Consumer Portfolio Segment | Student Loan | FICO at Origination | Less than 670 |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 293,025 | $ 328,199 |
Year 2 | 394,962 | 395,526 |
Year 3 | 261,589 | 208,696 |
Year 4 | 155,661 | 118,935 |
Year 5 | 94,355 | 137,494 |
After Year 5 | 475,186 | 451,613 |
Loan type | $ 1,674,778 | $ 1,640,463 |
% of Balance |  |  |
Private Education Loans at origination | 8.00% | 8.00% |
Consumer Portfolio Segment | Student Loan | FICO at Origination | 670-699 |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 615,617 | $ 635,642 |
Year 2 | 753,548 | 704,642 |
Year 3 | 449,214 | 400,744 |
Year 4 | 285,181 | 254,762 |
Year 5 | 197,205 | 257,840 |
After Year 5 | 898,535 | 868,777 |
Loan type | $ 3,199,300 | $ 3,122,407 |
% of Balance |  |  |
Private Education Loans at origination | 14.00% | 15.00% |
Consumer Portfolio Segment | Student Loan | FICO at Origination | 700-749 |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 1,525,547 | $ 1,383,779 |
Year 2 | 1,641,641 | 1,586,783 |
Year 3 | 998,834 | 934,033 |
Year 4 | 660,373 | 590,401 |
Year 5 | 451,695 | 545,333 |
After Year 5 | 1,782,121 | 1,709,299 |
Loan type | $ 7,060,211 | $ 6,749,628 |
% of Balance |  |  |
Private Education Loans at origination | 32.00% | 32.00% |
Consumer Portfolio Segment | Student Loan | FICO at Origination | Greater than or equal to 750 |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 2,590,403 | $ 2,142,499 |
Year 2 | 2,531,359 | 2,401,788 |
Year 3 | 1,475,610 | 1,393,949 |
Year 4 | 968,221 | 854,991 |
Year 5 | 630,741 | 691,633 |
After Year 5 | 2,104,385 | 2,028,486 |
Loan type | $ 10,300,719 | $ 9,513,346 |
% of Balance |  |  |
Private Education Loans at origination | 46.00% | 45.00% |
Consumer Portfolio Segment | Student Loan | FICO Refreshed |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 5,024,592 | $ 4,490,119 |
Year 2 | 5,321,510 | 5,088,739 |
Year 3 | 3,185,247 | 2,937,422 |
Year 4 | 2,069,436 | 1,819,089 |
Year 5 | 1,373,996 | 1,632,300 |
After Year 5 | 5,260,227 | 5,058,175 |
Loan type | $ 22,235,008 | $ 21,025,844 |
% of Balance |  |  |
Total in percent | 100.00% | 100.00% |
Consumer Portfolio Segment | Student Loan | FICO Refreshed | Less than 670 |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 453,705 | $ 495,451 |
Year 2 | 666,049 | 638,381 |
Year 3 | 467,562 | 379,738 |
Year 4 | 301,367 | 217,956 |
Year 5 | 194,124 | 214,665 |
After Year 5 | 831,053 | 791,875 |
Loan type | $ 2,913,860 | $ 2,738,066 |
% of Balance |  |  |
Private Education Loans at origination | 13.00% | 13.00% |
Consumer Portfolio Segment | Student Loan | FICO Refreshed | 670-699 |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 633,749 | $ 616,684 |
Year 2 | 710,546 | 672,777 |
Year 3 | 409,808 | 365,674 |
Year 4 | 248,325 | 193,462 |
Year 5 | 138,730 | 176,963 |
After Year 5 | 578,639 | 564,245 |
Loan type | $ 2,719,797 | $ 2,589,805 |
% of Balance |  |  |
Private Education Loans at origination | 12.00% | 12.00% |
Consumer Portfolio Segment | Student Loan | FICO Refreshed | 700-749 |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 1,485,771 | $ 1,347,094 |
Year 2 | 1,512,643 | 1,477,310 |
Year 3 | 879,450 | 836,747 |
Year 4 | 563,941 | 498,414 |
Year 5 | 362,715 | 445,244 |
After Year 5 | 1,398,737 | 1,361,073 |
Loan type | $ 6,203,257 | $ 5,965,882 |
% of Balance |  |  |
Private Education Loans at origination | 28.00% | 28.00% |
Consumer Portfolio Segment | Student Loan | FICO Refreshed | Greater than or equal to 750 |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 2,451,367 | $ 2,030,890 |
Year 2 | 2,432,272 | 2,300,271 |
Year 3 | 1,428,427 | 1,355,263 |
Year 4 | 955,803 | 909,257 |
Year 5 | 678,427 | 795,428 |
After Year 5 | 2,451,798 | 2,340,982 |
Loan type | $ 10,398,094 | $ 9,732,091 |
% of Balance |  |  |
Private Education Loans at origination | 47.00% | 47.00% |
Consumer Portfolio Segment | Student Loan | Seasoning |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 5,024,592 | $ 4,490,119 |
Year 2 | 5,321,510 | 5,088,739 |
Year 3 | 3,185,247 | 2,937,422 |
Year 4 | 2,069,436 | 1,819,089 |
Year 5 | 1,373,996 | 1,632,300 |
After Year 5 | 5,260,227 | 5,058,175 |
Loan type | $ 22,235,008 | $ 21,025,844 |
% of Balance |  |  |
Total in percent | 100.00% | 100.00% |
Consumer Portfolio Segment | Student Loan | Seasoning | 1-12 payments |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 2,860,113 | $ 2,514,079 |
Year 2 | 774,471 | 740,450 |
Year 3 | 499,812 | 440,293 |
Year 4 | 280,154 | 245,631 |
Year 5 | 159,762 | 208,941 |
After Year 5 | 324,506 | 332,608 |
Loan type | $ 4,898,818 | $ 4,482,002 |
% of Balance |  |  |
Seasoning based on monthly scheduled payments due from 1-12 payments | 22.00% | 21.00% |
Consumer Portfolio Segment | Student Loan | Seasoning | 13-24 payments |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 0 | $ 0 |
Year 2 | 2,729,334 | 2,675,956 |
Year 3 | 372,496 | 303,045 |
Year 4 | 191,989 | 167,532 |
Year 5 | 122,938 | 165,577 |
After Year 5 | 340,556 | 384,760 |
Loan type | $ 3,757,313 | $ 3,696,870 |
% of Balance |  |  |
Seasoning based on monthly scheduled payments due from 13 - 24 payments | 17.00% | 18.00% |
Consumer Portfolio Segment | Student Loan | Seasoning | 25-36 payments |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 0 | $ 0 |
Year 2 | 0 | 0 |
Year 3 | 1,564,157 | 1,524,834 |
Year 4 | 254,068 | 195,091 |
Year 5 | 110,952 | 129,571 |
After Year 5 | 429,127 | 456,448 |
Loan type | $ 2,358,304 | $ 2,305,944 |
% of Balance |  |  |
Seasoning based on monthly scheduled payments due from 25 - 36 payments | 11.00% | 11.00% |
Consumer Portfolio Segment | Student Loan | Seasoning | 37-48 payments |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 0 | $ 0 |
Year 2 | 0 | 0 |
Year 3 | 0 | 0 |
Year 4 | 987,977 | 902,938 |
Year 5 | 170,051 | 208,521 |
After Year 5 | 451,494 | 446,350 |
Loan type | $ 1,609,522 | $ 1,557,809 |
% of Balance |  |  |
Seasoning based on monthly scheduled payments due from 37 - 48 payments | 7.00% | 7.00% |
Consumer Portfolio Segment | Student Loan | Seasoning | More than 48 payments |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 0 | $ 0 |
Year 2 | 0 | 0 |
Year 3 | 0 | 0 |
Year 4 | 0 | 116 |
Year 5 | 625,916 | 706,097 |
After Year 5 | 3,262,308 | 2,985,015 |
Loan type | $ 3,888,224 | $ 3,691,228 |
% of Balance |  |  |
Seasoning based on monthly scheduled payments due from more than 48 payments | 17.00% | 18.00% |
Consumer Portfolio Segment | Student Loan | Seasoning | Not yet in repayment |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Year 1 | $ 2,164,479 | $ 1,976,040 |
Year 2 | 1,817,705 | 1,672,333 |
Year 3 | 748,782 | 669,250 |
Year 4 | 355,248 | 307,781 |
Year 5 | 184,377 | 213,593 |
After Year 5 | 452,236 | 452,994 |
Loan type | $ 5,722,827 | $ 5,291,991 |
% of Balance |  |  |
Seasoning based on monthly scheduled payments due from not yet in repayment | 26.00% | 25.00% |

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