| **COMMITMENTS, CONTINGENCIES AND GUARANTEES (Tables)**       | 6 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 June 30, 2016 December 31, 2015  (in thousands)Commitments to extend credit (1) $22,886,984 $31,379,039Letters of credit 1,824,432 1,832,884Recourse exposure on sold loans 71,682 70,394Commitments to sell loans 104,475 56,982Total commitments $24,887,573 $33,339,299(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:  June 30, 2016 December 31, 2015  (in thousands)1 year or less $4,557,649 $6,451,239Over 1 year to 3 years 4,690,687 5,250,512Over 3 years to 5 years 5,158,780 12,136,625Over 5 years (1) 8,479,868 7,540,663Total $22,886,984 $31,379,039(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:   June 30, 2016 December 31, 2015  (in thousands)1 year or less $1,349,822 $1,230,424Over 1 year to 3 years 352,120 308,634Over 3 years to 5 years 97,783 268,946Over 5 years 24,707 24,880Total $1,824,432 $1,832,884                                                                                                                                                                                        |

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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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No definition available.
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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.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(e),(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690
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