| **COMMITMENTS, CONTINGENCIES, AND GUARANTEES (Tables)**         | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| **Commitments and Contingencies Disclosure [Abstract]**         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Schedule of Commitments Amount                                  | The following table details the amount of commitments at the dates indicated: Other Commitments December 31, 2015 December 31, 2014  (in thousands)Commitments to extend credit (1) $31,379,039 $28,792,062Unsecured revolving lines of credit — 5Letters of credit 1,832,884 1,789,666Recourse exposure on sold loans 70,394 174,902Commitments to sell loans 56,982 82,791Total commitments $33,339,299 $30,839,426(1) Commitments to extend credit excludes commitments that can be canceled by the Company without notice.                                                           |
| Schedule of Commitments to Extend Credit, Expiration Periods    | The following table details the amount of commitments to extend credit expiring per period as of the dates indicated:  December 31, 2015 December 31, 2014  (in thousands)1 year or less $6,451,239 $5,968,468Over 1 year to 3 years 5,250,512 5,322,291Over 3 years to 5 years 12,136,625 10,810,213Over 5 years (1) 7,540,663 6,691,090Total $31,379,039 $28,792,062 (1)Includes certain commitments to extend credit that do not have a contractual maturity date, but are expected to be outstanding greater than 5 years.                                                            |
| Schedule of Letters of Credit, Expiration Periods               | The following table details the amount of letters of credit expiring per period as of the dates indicated:   December 31, 2015 December 31, 2014  (in thousands)1 year or less $1,230,424 $1,250,124Over 1 year to 3 years 308,634 285,108Over 3 years to 5 years 268,946 248,209Over 5 years 24,880 6,225Total $1,832,884 $1,789,666                                                                                                                                                                                                                                                          |
| Schedule of Future Minimum Rental Payments for Operating Leases | Future minimum annual rentals under non-cancelable operating leases and sale-leaseback leases, net of expected sublease income, at December 31, 2015, are summarized as follows:  AT DECEMBER 31, 2015  LeasePayments Future MinimumExpected  SubleaseIncome NetPayments  (in thousands)2016 $125,672 $(7,403) $118,2692017 115,247 (6,925) 108,3222018 99,016 (4,840) 94,1762019 87,106 (3,932) 83,1742020 64,564 (2,414) 62,150Thereafter 262,901 (5,793) 257,108Total $754,506 $(31,307) $723,199 |

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| - Definition
Tabular disclosure of commitments and contingencies by maturities.
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| - Definition
Tabular disclosure of information about obligations resulting from other commitments.
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| - Definition
Tabular disclosure of future minimum payments required in the aggregate and for each of the five succeeding fiscal years for operating leases having initial or remaining noncancelable lease terms in excess of one year and the total minimum rentals to be received in the future under noncancelable subleases as of the balance sheet date.
+ References
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| - Definition
Tabular disclosure of short-term or long-term contractual arrangements with lenders, including letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line.
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