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Fair Value Measurements - Fair Values of Financial Assets and Liabilities, Including Derivative Financial Instruments (Detail) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Earning assets: |  |
Loans held for sale | $ 0 | $ 0
Trading investments | 54,481 | 55,903
Accrued interest receivable, difference | 68,862 | 35,015
Tax indemnification receivable | 366,247 | 380,058
Derivative instruments | 0 | 405
Total earning assets, difference | 2,534,325 | 2,088,881
Interest-bearing liabilities: |  |
Long-term borrowings, difference | 353,822 | 421,881
Derivative instruments | 370 | 0
Total interest-bearing liabilities, difference | 489,912 | 838,340
Excess of net asset fair value over carrying value | 3,024,237 | 2,927,221
Money-market and savings accounts |  |
Interest-bearing liabilities: |  |
Certificates of deposits, difference | 68,409 | 104,979
Certificates of Deposit |  |
Interest-bearing liabilities: |  |
Certificates of deposits, difference | 67,681 | 311,480
Fair Value |  |
Earning assets: |  |
Loans held for sale | 0 | 29,448
Cash and cash equivalents | 4,149,838 | 4,616,117
Trading investments | 54,481 | 55,903
Available-for-sale investments | 2,411,622 | 2,342,089
Accrued interest receivable | 1,448,766 | 1,237,074
Tax indemnification receivable | 0 | 2,816
Derivative instruments | 0 | 972
Total | 30,836,527 | 29,965,153
Interest-bearing liabilities: |  |
Long-term borrowings | 4,873,690 | 4,813,233
Accrued interest payable | 105,066 | 71,586
Derivative instruments | 370 | 567
Total interest-bearing liabilities | 26,494,693 | 25,915,574
Fair Value | Money-market and savings accounts |  |
Interest-bearing liabilities: |  |
Deposits | 11,134,883 | 11,854,849
Fair Value | Certificates of Deposit |  |
Interest-bearing liabilities: |  |
Deposits | 10,380,684 | 9,175,339
Carrying Value |  |
Earning assets: |  |
Loans held for sale | 0 | 29,448
Cash and cash equivalents | 4,149,838 | 4,616,117
Trading investments | 54,481 | 55,903
Available-for-sale investments | 2,411,622 | 2,342,089
Accrued interest receivable | 1,379,904 | 1,202,059
Tax indemnification receivable | 0 | 2,816
Derivative instruments | 0 | 972
Total | 28,302,202 | 27,876,272
Interest-bearing liabilities: |  |
Long-term borrowings | 5,227,512 | 5,235,114
Accrued interest payable | 105,066 | 71,586
Derivative instruments | 370 | 567
Total interest-bearing liabilities | 26,984,605 | 26,753,914
Carrying Value | Money-market and savings accounts |  |
Interest-bearing liabilities: |  |
Deposits | 11,203,292 | 11,959,828
Carrying Value | Certificates of Deposit |  |
Interest-bearing liabilities: |  |
Deposits | 10,448,365 | 9,486,819
Private Education Loans |  |
Earning assets: |  |
Loans held for investment, net, difference | 2,456,752 | 2,042,835
Private Education Loans | Fair Value |  |
Earning assets: |  |
Private Education Loans | 22,229,045 | 21,062,548
Private Education Loans | Carrying Value |  |
Earning assets: |  |
Private Education Loans | 19,772,293 | 19,019,713
FFELP Loans |  |
Earning assets: |  |
Loans held for investment, net, difference | 8,711 | 11,031
FFELP Loans | Fair Value |  |
Earning assets: |  |
Private Education Loans | 542,775 | 618,186
FFELP Loans | Carrying Value |  |
Earning assets: |  |
Private Education Loans | $ 534,064 | $ 607,155

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- Definition Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities. + References No definition available. + Details
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