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Loans Receivable and Allowance for Loan Losses - Loans Receivable Delinquencies (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018 | Sep. 30, 2018
--- | --- | --- | ---
Loans in repayment status: |  |  |
Total loans | $ 21,206,948 | $ 22,520,498 |
Federally insured loans |  |  |
Loans in repayment status: |  |  |
Total loans | 20,695,837 | 22,155,896 |
Federally insured loans | Federally insured loans |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans in-school/grace/deferment | 1,243,705 | 1,298,493 | $ 1,410,902
Loans in forbearance | 1,391,482 | 1,430,291 | 1,487,107
Loans in repayment status: |  |  |
Loans current | 15,646,231 | 16,882,252 | 16,921,119
Total loans in repayment | $ 18,060,650 | $ 19,427,112 | $ 19,492,734
Loans current, percentage | 86.70% | 86.90% | 86.80%
Total loans in repayment, percentage | 100.00% | 100.00% | 100.00%
Total loans | $ 20,695,837 | $ 22,155,896 | $ 22,390,743
Federally insured loans | Loans delinquent 31-60 days | Federally insured loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 662,431 | $ 683,084 | $ 689,454
Loans past due, percentage | 3.80% | 3.50% | 3.50%
Federally insured loans | Loans delinquent 61-90 days | Federally insured loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 402,197 | $ 427,764 | $ 412,639
Loans past due, percentage | 2.20% | 2.20% | 2.10%
Federally insured loans | Loans delinquent 91-120 days | Federally insured loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 279,524 | $ 283,831 | $ 347,013
Loans past due, percentage | 1.50% | 1.50% | 1.80%
Federally insured loans | Loans delinquent 121-270 days | Federally insured loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 795,230 | $ 806,692 | $ 853,224
Loans past due, percentage | 4.40% | 4.20% | 4.40%
Federally insured loans | Loans delinquent 271 days or greater | Federally insured loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 275,037 | $ 343,489 | $ 269,285
Loans past due, percentage | 1.40% | 1.70% | 1.40%
Private education loans |  |  |
Loans in repayment status: |  |  |
Total loans | $ 189,912 | $ 225,975 |
Private education loans | Private education loans |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans in-school/grace/deferment | 3,944 | 4,320 | $ 3,550
Loans in forbearance | 2,242 | 1,494 | 1,577
Loans in repayment status: |  |  |
Loans current | 173,883 | 208,977 | 156,383
Total loans in repayment | $ 183,726 | $ 220,161 | $ 164,340
Loans current, percentage | 94.70% | 95.00% | 95.20%
Total loans in repayment, percentage | 100.00% | 100.00% | 100.00%
Total loans | $ 189,912 | $ 225,975 | $ 169,467
Private education loans | Loans delinquent 31-60 days | Private education loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 3,011 | $ 3,626 | $ 1,796
Loans past due, percentage | 1.60% | 1.60% | 1.10%
Private education loans | Loans delinquent 61-90 days | Private education loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 1,370 | $ 1,560 | $ 1,155
Loans past due, percentage | 0.70% | 0.70% | 0.70%
Private education loans | Loans delinquent 91 days or greater | Private education loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 5,462 | $ 5,998 | $ 5,006
Loans past due, percentage | 3.00% | 2.70% | 3.00%
Consumer loans |  |  |
Loans in repayment status: |  |  |
Total loans | $ 321,199 | $ 138,627 |
Consumer loans | Consumer loans |  |  |
Loans in repayment status: |  |  |
Loans current | 315,708 | 136,130 | $ 110,885
Total loans in repayment | $ 321,199 | $ 138,627 | $ 112,547
Loans current, percentage | 98.30% | 98.20% | 98.50%
Total loans in repayment, percentage | 100.00% | 100.00% | 100.00%
Total loans | $ 321,199 | $ 138,627 | $ 112,547
Consumer loans | Loans delinquent 31-60 days | Consumer loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 2,249 | $ 1,012 | $ 905
Loans past due, percentage | 0.70% | 0.70% | 0.80%
Consumer loans | Loans delinquent 61-90 days | Consumer loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 1,617 | $ 832 | $ 355
Loans past due, percentage | 0.50% | 0.60% | 0.30%
Consumer loans | Loans delinquent 91 days or greater | Consumer loans |  |  |
Loans in repayment status: |  |  |
Loans past due | $ 1,625 | $ 653 | $ 402
Loans past due, percentage | 0.50% | 0.50% | 0.40%

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