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Allowance for Credit Losses - Allowance and Recorded Investments in Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021 | Dec. 31, 2021
Allowance for Credit Losses |  |  |  |  |
Beginning balance | $ 1,227,362 | $ 1,179,021 | $ 1,165,335 | $ 1,361,723 | $ 1,361,723
Transfer from unfunded commitment liability | 40,528 | 24,556 | 135,214 | 151,436 |
Provision for current period | 25,050 | 1,194 | 73,668 | (253,805) |
Loan sale reduction to provision | (115,852) | (1,477) | (121,099) | (10,335) |
Loan transfer from held-for-sale |  |  |  | 1,887 |
Total provisions | (90,802) | (283) | (47,431) | (262,253) |
Net charge-offs: |  |  |  |  |
Charge-offs | (106,999) | (50,028) | (191,065) | (105,344) |
Recoveries | 10,977 | 6,978 | 19,013 | 14,682 |
Net charge-offs | (96,022) | (43,050) | (172,052) | (90,662) |
Ending Balance | 1,081,066 | 1,160,244 | 1,081,066 | 1,160,244 | 1,165,335
Allowance |  |  |  |  |
Ending balance: individually evaluated for impairment | 0 | 80,495 | 0 | 80,495 |
Ending balance: collectively evaluated for impairment | 1,081,066 | 1,079,749 | 1,081,066 | 1,079,749 |
Loans: |  |  |  |  |
Ending balance: individually evaluated for impairment | 0 | 1,192,743 | 0 | 1,192,743 |
Ending balance: collectively evaluated for impairment | 20,213,751 | 20,014,756 | 20,213,751 | 20,014,756 |
Private Education Loan provision for credit losses, other impacts | 519 | 180 | 677 | 123 |
Less: provisions for credit losses | 30,545 | 69,677 | 128,595 | (156,090) |
FFELP Loans |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Beginning balance | 3,999 | 4,318 | 4,077 | 4,378 | 4,378
Transfer from unfunded commitment liability | 0 | 0 | 0 | 0 |
Provision for current period | 60 | (2) | 81 | 27 |
Loan sale reduction to provision | 0 | 0 | 0 | 0 |
Loan transfer from held-for-sale |  |  |  | 0 |
Total provisions | 60 | (2) | 81 | 27 |
Net charge-offs: |  |  |  |  |
Charge-offs | (130) | (54) | (229) | (143) |
Recoveries | 0 | 0 | 0 | 0 |
Net charge-offs | (130) | (54) | (229) | (143) |
Ending Balance | 3,929 | 4,262 | 3,929 | 4,262 | 4,077
Allowance |  |  |  |  |
Ending balance: individually evaluated for impairment | 0 | 0 | 0 | 0 |
Ending balance: collectively evaluated for impairment | 3,929 | 4,262 | 3,929 | 4,262 |
Loans: |  |  |  |  |
Ending balance: individually evaluated for impairment | 0 | 0 | 0 | 0 |
Ending balance: collectively evaluated for impairment | $ 665,666 | $ 716,958 | $ 665,666 | $ 716,958 |
Net charge-offs as a percentage of average loans in repayment (annualized) | 0.10% | 0.04% | 0.08% | 0.05% |
Allowance as a percentage of the ending total loan balance | 0.59% | 0.59% | 0.59% | 0.59% |
Allowance as a percentage of the ending loans in repayment | 0.73% | 0.78% | 0.73% | 0.78% |
Allowance coverage of net charge-offs (annualized) | 7.56 | 19.73 | 8.58 | 14.90 |
Ending total loans, gross | $ 665,666 | $ 716,958 | $ 665,666 | $ 716,958 |
Average loans in repayment | 537,449 | 546,306 | 541,133 | 551,765 |
Ending loans in repayment | 538,081 | 548,488 | 538,081 | 548,488 |
Private Education Loan provision for credit losses, other impacts | 60 | (2) | 81 | 27 |
Private Education Loans |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Beginning balance | 1,221,053 | 1,173,375 | 1,158,977 | 1,355,844 | 1,355,844
Transfer from unfunded commitment liability | 40,528 | 24,556 | 135,214 | 151,436 |
Provision for current period | 24,531 | 1,014 | 72,991 | (253,928) |
Loan sale reduction to provision | (115,852) | (1,477) | (121,099) | (10,335) |
Loan transfer from held-for-sale |  |  |  | 1,887 |
Total provisions | (91,321) | (463) | (48,108) | (262,376) |
Net charge-offs: |  |  |  |  |
Charge-offs | (106,493) | (49,900) | (190,349) | (105,039) |
Recoveries | 10,977 | 6,972 | 19,010 | 14,675 |
Net charge-offs | (95,516) | (42,928) | (171,339) | (90,364) |
Ending Balance | 1,074,744 | 1,154,540 | 1,074,744 | 1,154,540 | 1,158,977
Allowance |  |  |  |  |
Ending balance: individually evaluated for impairment | 0 | 80,495 | 0 | 80,495 |
Ending balance: collectively evaluated for impairment | 1,074,744 | 1,074,045 | 1,074,744 | 1,074,045 |
Loans: |  |  |  |  |
Ending balance: individually evaluated for impairment | 0 | 1,192,743 | 0 | 1,192,743 |
Ending balance: collectively evaluated for impairment | $ 19,519,185 | $ 19,285,014 | $ 19,519,185 | $ 19,285,014 |
Net charge-offs as a percentage of average loans in repayment (annualized) | 2.56% | 1.16% | 2.23% | 1.23% |
Allowance as a percentage of the ending total loan balance | 5.51% | 5.64% | 5.51% | 5.64% |
Allowance as a percentage of the ending loans in repayment | 7.40% | 7.79% | 7.40% | 7.79% |
Allowance coverage of net charge-offs (annualized) | 2.81 | 6.72 | 3.14 | 6.39 |
Ending total loans, gross | $ 19,519,185 | $ 20,477,757 | $ 19,519,185 | $ 20,477,757 |
Average loans in repayment | 14,901,040 | 14,743,360 | 15,366,023 | 14,738,505 |
Ending loans in repayment | 14,525,259 | 14,825,375 | 14,525,259 | 14,825,375 |
Provisions for loan losses | (91,321) | (463) | (48,108) | (262,376) |
Provisions for unfunded loan commitments | 121,347 | 69,960 | 176,026 | 106,163 |
Total Private Education Loan provisions for credit losses | 30,026 | 69,497 | 127,918 | (156,213) |
Credit Cards |  |  |  |  |
Allowance for Credit Losses |  |  |  |  |
Beginning balance | 2,310 | 1,328 | 2,281 | 1,501 | 1,501
Transfer from unfunded commitment liability | 0 | 0 | 0 | 0 |
Provision for current period | 459 | 182 | 596 | 96 |
Loan sale reduction to provision | 0 | 0 | 0 | 0 |
Loan transfer from held-for-sale |  |  |  | 0 |
Total provisions | 459 | 182 | 596 | 96 |
Net charge-offs: |  |  |  |  |
Charge-offs | (376) | (74) | (487) | (162) |
Recoveries | 0 | 6 | 3 | 7 |
Net charge-offs | (376) | (68) | (484) | (155) |
Ending Balance | 2,393 | 1,442 | 2,393 | 1,442 | $ 2,281
Allowance |  |  |  |  |
Ending balance: individually evaluated for impairment | 0 | 0 | 0 | 0 |
Ending balance: collectively evaluated for impairment | 2,393 | 1,442 | 2,393 | 1,442 |
Loans: |  |  |  |  |
Ending balance: individually evaluated for impairment | 0 | 0 | 0 | 0 |
Ending balance: collectively evaluated for impairment | $ 28,900 | $ 12,784 | $ 28,900 | $ 12,784 |
Net charge-offs as a percentage of average loans in repayment (annualized) | 5.33% | 2.29% | 3.54% | 2.59% |
Allowance as a percentage of the ending total loan balance | 8.28% | 11.28% | 8.28% | 11.28% |
Allowance as a percentage of the ending loans in repayment | 8.28% | 11.28% | 8.28% | 11.28% |
Allowance coverage of net charge-offs (annualized) | 1.59 | 5.30 | 2.47 | 4.65 |
Ending total loans, gross | $ 28,900 | $ 12,784 | $ 28,900 | $ 12,784 |
Average loans in repayment | 28,243 | 11,855 | 27,375 | 11,964 |
Ending loans in repayment | 28,900 | 12,784 | 28,900 | 12,784 |
Private Education Loan provision for credit losses, other impacts | $ 459 | $ 182 | $ 596 | $ 96 |

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